Lum, Ten, and Lum's father from Urusei Yatsura speak Japanese, but Lum's mother cannot (her speech is rendered as Mahjong tiles). Rei can say just a few words, and Lum forgets Japanese for an episode after getting hit by a baseball. But... practically every alien other than Lum's mother is fluent. Benten, Oyuki, Ran, Elle, the taxi driver...
All those aliens in To Love-Ru seem to have their Japanese down just fine. Although apparently it did take some time for Lala to learn the written language. And English for that matter, when Pikari lands in America and converses with a gingercowgirl.
For some reason, intergalactic demons from Dragon Ball Z seem to speak impeccable Japanese (or whatever the language of the version you're watching), although at times, various aliens speak their native tongue, such as Frieza, though it makes you wonder why they choose to speak the earthings' language in the first place. The Namekians also have their own native language, as one of the village elders speaks it to try and confuse Frieza, although Frieza is well aware of the fact that he can speak Japanese. Also, the Namekian dragon can only be released by a password spoken in Namekian and wishes can only be made in the Namekian language. This is made more confusing by the fact that the Dragon itself speaks normal Japanese.
The English dub mentions a "Universal Language", but this isn't in the Japanese version.
Fan theories have it that the scouters used by most of the alien species in Frieza's employ also double as translator devices.
Dragon Ball Abridged plays with this just like everything else, stating that English is the universal language. They also fix the issue with Porunga by having him speak only Namekian (which sounds suspiciously like Klingon), though he is later taught English to make granting wishes more convenient for the heroes.
Even in Japanese. Tony somehow speaks better English than anglo countries do! Which perhaps is more of positive reflection upon Tony's actor compared to the rest of them, than it is a negative one upon the characters themselves.
The Human Aliens in Lyrical Nanoha speak Japanese. Their computers speakEnglish (or German). Think about that for a second. Although magic enables telepathy, so a translation effect as an extension of that makes a certain amount of sense. As for the devices, one can assume that they are speaking Midchildan or Belkan, rendered into English or German for the sake of aesthetics. In the non-translated manga; a random TSAB team training in the field is singing a marching song in English. It would seem actual English is the language the TSAB speaks.
In Vandread, this is half played straight as every population speaks (or telepathicallythinks) in the same language, but the Mejerran pirates can't read Tarak computer panels. This is intentional. Both planets speak Japanese, but the Majarrians write only in kana, and the Tarakkians write only in kanji. It's a backhanded reference to a popular treatise on the Japanese language published in the 1950s; in one passage it compares instances of male and female writing that approach this extreme, and remarks that to look at them you'd scarcely think they were in the same language.
Villains in Sailor Moon are often Aliens. The first anime's hell tree arc, the Death Busters and Shadow Galactica are all full of them. As are the Villains of all 3 Movies. Aside from a single gag during the Hell Tree Arc, none of them show any signs of speaking anything but perfect Japanese. The Musicals also have new alien characters though this may be to Media limitations (You can't have subtitles in a live show.) The Death Busters were possessed humans. As for the rest, if even the cats can speak the local language, it's best not to think about it too hard.
Also in Gintama the aliens already managed to take over the world but for some reason they all learned Japanese instead of making the humans learn their language. However, there seem to be quite a few different species of aliens, so they might have just all learned the language of the oppressed to spare them the possibly multiple language courses.
When the girls of Magic Knight Rayearth are transported to Cephiro, they seem to take it for granted that everyone speaks Japanese. That is, until they meet Caldina and notice her Kansai Regional Accent. Then they start asking if there's an Osaka in Cephiro too.
Even though she's not an alien (maybe ...) Ika is believed to be able to speak Japanese because she lived in Japanese coastal waters until coming ashore. She also picks up English really quick.
Lampshaded in Sgt. Frog. Keroro and other keronians/aliens (like mois) speak perfect Japanese/English. When asked about this by Fuyuki he counters by saying that Japanese/English sounds like Keronian.
Used in Dears when Ren learns Japanese in one night by reading a single Japanese textbook. Justified because it's a genetic trait programmed into the Dears to learn languages. How this also allows her to SPEAK Japanese however is never explained
In Narue No Sekai, the Human Aliens all speak Japanese - because they come from Planet Japan, which has undergone some strange convergent evolution such that they are linguistically and culturally (and biologically) identical to modern-day Japan. Actually, nearly every alien homeworld corresponds to some Earth nation in the same way, the possible implications of which baffle and disturb the aliens to no end because Earth has somehow miraculously not destroyed itself while interstellar society is on the edge of constant warfare - and that's with light years of breathing room between each society!
The Pillarmen of JoJo's Bizarre Adventure Part II aren't aliens, being a race of ancient superhumans, but otherwise fit the bill. The weakest and least intelligent one, Santana, is able to speak full sentences using modern language after overhearing a few conversations. All after a four thousand year slumber. The stronger ones pick up modern language immediately after hearing a few words.
Justified in the Marvel Comics series Sleepwalker, when the eponymous alien hero learns to speak English because that's the language his human host speaks. The letters page stated that if Sleepwalker had been trapped in the mind of someone who spoke another language, like French or German, he would have begun using that language when he first appeared in the human world.
One Silver AgeJimmy Olsen story in The DCU had Jimmy stranded on an alien world where everyone spoke English. The explanation? They had studied the universe's languages and adopted English as the most efficient! The mind boggles!
The Scrameustache justifies the language thing; the aliens have devices which allow them to learn any language in minutes (first time Khena encountered them, conversation took place in their language, because they had used the device on him while he was sleeping). But the "Aliens have our culture" trope is exagerated if not parodied: the alien medic wears a red cross!
Occurs without explanation in Zita The Spacegirl. Granted, Zita and (possibly) Joseph are smart kids who are quick on the uptake, but not that quick. A few of the alien background characters do seem to speak their own languages, curiously enough.
The Teenage Mutant Ninja Turtles leave the planet and immediately come upon robots and aliens that speak English (and, in the same town, some who don't).
In ElfQuest the elves and trolls speak the same language but humans don't - at least, initially. In the later series the humans seem to be speaking the same language, having possibly learned it from elves along the way. Or something.
In Paperinik New Adventures Evronians, Xerbians and other alien races speak fluently the Language of the protagonist. He once lampshades it, and one alien (a Grilk) explain that his training included other worlds's languages. For the Others, Word of God states that they learned it from watching sci-fi movies.
When the four arrive on C'hou in With Strings Attached, they immediately meet people who speak accented English (much to their relief). Everywhere else they go, everyone speaks English. However, early on, John and Ringo encounter several books in other languages, and Stal mentions that some names (Idri'en Tagen and Raleka) are “old language names.” And different races have different styles of names, suggesting derivation from different languages. As the four have other things to think about and are not linguists, they never delve into this topic.
The Star Wars fanfilms TROOPS and IMPS both avert the trope by having various aliens speak in their own language while the stormtroopers speak English/Basic.
What with how common the "Humans in Equestria" plot is in My Little Pony: Friendship Is Magic fanfiction is, this is fairly common. However, as time goes on, aversions and subversions become more common. Sometimes spoken language is perfectly understandable, but the written word seems to follow a different alphabet, following the show. Sometimes some sort of language spell is employed, or if you have a "first contact" type story, you do see the ponies and humans over-coming the language barrier.
Momentarily played with in the Transformers fanfic Eugenesis, where mention is made of someone scrawling graffiti on a building in what to us would read like German, several million years before the German language even existed. Apart from that, though, pretty much everyone speaks English.
The Lord of the Rings is a bit of a mix with this. Obviously justified in that the audience will only understand it if it's in English, but there are still some inconsistencies:
When Aragorn and Arwen talk to each other, they normally speak Sindarin. This would make sense, as it's Arwen's and presumably Aragorn's (as he was raised by elves) first language. But that would also be the case with Aragorn and Legolas, yet they still speak Westron/English even when they're the only people present. Elrond and Aragorn begin a conversation in Westron and finish it in Sindarin.
The Rohirrim and the Orcs, both of whom have separate native languages in the books, only speak English in the films.
Jake, the alien cat from The Cat From Outer Space "speaks" English using a form of telepathy thanks to his translator collar.
The Transformers in the live-action Transformers film assimilated languages from the world wide web. Word of God states that Megatron, who was frozen inside the Hoover Dam since its construction, picked up languages from the nearby scientists and engineers. Weirdly enough, in the second film, Megatron and Starscream have entire conversations in plain English despite not talking to any humans in particular. In the novelization of the first film Optimus tries to speak Mandarin Chinese to Sam and Mikaela when they meet, which the teens hypothesize that he's trying the language with the highest number of speakers on Earth.
Some of the finer moments in the original trilogy are when this trope is inverted: two characters converse, each in their own language, with no subtitles provided - Han and Chewie throughout; Uncle Owen and the Jawas, Han and Greedo at Mos Eisley; Han and Jabba in Docking Bay 94; the "spy" and stormtroopers at Mos Eisley; C-3PO and R2-D2 throughout; Luke and R2-D2, Han and the droid at the beginning of The Empire Strikes Back; C-3PO and the other protocol droid at Bespin; C-3PO and Jabba on Tatooine, Luke and Jabba on Tatooine; and Lando conversing with his copilot in Return of The Jedi come to mind.
The beginning of The Phantom Menace could have used a lot more of this. It did have at least one instance however, Little Annie and Sebulba.
It's explained in the expanded universe that "Basic" is the human language, and because of demographics, the common interspecies language. However, some non-humans can understand basic but not speak it. Inverted in one of the Expanded Universe novels when Leia goes to Kashyyyk and has difficultly understanding the Wookiees, aside from one, a professional greeter who explains rather sheepishly that he has a speech impediment which makes it easier for "Basic Speakers" to understand. The Greek alphabet also appears in various instances in the EU. The appearance of Greek letters in-universe was eventually explained as being called the Tionese alphabet (Tion being a planet that already existed in SW lore and was of some significance at some point in the galaxy's history).
In the first edition, there were some English words on computer screens. Replaced by the fictional alphabet Aurebesh in DVD edition.
Darth Vader's chestplate has Hebrew script on it, and has since the beginning, so they've never relied entirely on the Roman alphabet. Always relied on Earthern alphabets, yes, but not always roman.
Earth Girls Are Easy had the furry human aliens learning English via television - resulting in them imitating Jerry Lewis and James Dean, and asking questions like "Are we limp and hard to manage?"
Centauri from The Last Starfighter apparently speaks English without the need for a translator device. Though considering the fact that he had to have spent considerable time on Earth while developing and marketing the Starfighter video game, it makes sense. Also handwaved for most of the entire outer space portion of the movie as one of the first things Alex Rogan has done is have a 'translator' embedded in him - so the aliens are not speaking English… he's hearing them in English. The Ko-Dan still talk amongst each other in English, although this is likely standard Translation Convention.
The Transylvanians in The Rocky Horror Picture Show are all capable of both speaking (and singing) in English. It's implied they learned how to speak English from watching old "B" movies such as King Kong.
In Avatar it's explained Grace opened up a school for the Na'vi and taught them English several years before the film opened. The school was also shut down some time before the film started.
Justified in Buckaroo Banzai. The Red Lectroids originally came to the U.S. back in 1938, so they've had plenty of time to learn English. The Black Lectroids have apparently been studying the Earth for a long time while they were keeping an eye on the Red Lectroid refugees.
In Galaxy Quest, everything has been learnt by the aliens from "the historical documents". The Thermians still had to use translators (Laliari's broke down in the limo). Presumably, Sarris had one as well. Especially since it's unlikely his Lizard Folk race have something called "tissue paper". It's likely he used his own race's material with similar structure, and the translator rendered it as "tissue paper".
Not truly aliens per se but Atlantians in Atlantis: The Lost Empire magically know every language even though they've been isolated from society for centuries. The attempted justification for this is that the Atlantean language is apparently the mother tongue from which all European languages are descended. This makes about as much sense as someone from ancient Rome being fluent in Spanish, Portuguese, Italian, French, and Romanian without any prior exposure to said languages.
Planet 51: Lem and Chuck tell each other "You speak ... my language." Some viewers expect a "Rigelian" joke a la The Simpsons (see Western Animation below), but the native name remains unrevealed.
Predators in the Predator movies record, play back and imitate human phrases, but never come up with their own. It's left a bit murky as to how well they actually understand what they're saying, but it's usually good enough to lure unwary humans into their grasp. They understand it enough to make an Ironic Echo when appropriate. At the end of Predator 2 one alien messes with a necklace (translator device?) before saying 'Take it. Keep it.' (although only "take it" is subtitled) and handing over a duelling pistol.
Lampshaded in Paul, as demonstrated by the page quote, who has had several decades to learn the language.
Played with in Starman, where the title character knows some of Earth's languages, but only from what was aboard Voyager II. Hilarity Ensues as he tries to comprehend simple phrases such as "Take it easy". He is a bit more fluent by the end, but still speaks in broken sentences.
In the Soviet sci-fi classic Teens in the Universe, both the Cassiopeians and their Ridiculously Human Robots initially communicate in short whistles that are translated by the teens' Soviet-made translation device (the device can even translate dog barks). One of the teens even mentions in her log that the whistles are indistinguishable to the human ear. The robots quickly switch to English after observing humans for a short while... and even communicate amongst one another in English instead of their normal whistles. The Cassiopeians are quickly able to learn English after asking the teens to give them the Russian alphabet and a list of commonly-used words, which the translation device provides. Funny enough, when Lob tries to communicate with two robots by writing out a mathematical formula, one of the robots corrects his mistake, which indicates that they understand Latin alphabet, Arabic numerals, and mathematical symbols. Their own writing is incomprehensible to humans.
In Man of Steel, the scenes on Krypton could have been Translation Convention, and of course Clark has spent nearly his whole life on Earth, but it gets a little weird when the other Kryptonians have little trouble speaking perfect English as soon as they land. The landing message demanding Clark's surrender was broadcast all over the world, shown in whatever the native language of the area is. We can assume that they've figured out how to communicate in whatever languages are necessary.
When Thor arrives on Earth, he wakes up and start speaking English, even when logic may indicate that the Asgardians speak Old Norse or a similar language. Thor could have learned English in some moment of his past but this is never even hinted at in the film.
Two aliens are sitting in a pub. One of them turns to the other and says, ‘plububulaBBHAJGGIUI@@#GJKG?’ The other one replies, ‘Dude, you are seriously shitfaced.’
The Starcraft novel Queen of Blades (by Aaron Rosenberg) seems to have a bad case of this, with Jim Raynor encountering Zerg Cerebrates and Overlords that speak aloud in English, conveniently letting him eavesdrop. It turns out he was actually unconsciously hearing their telepathic voices through his latent connection to Kerrigan. Zeratul even comments that the Zerg don't speak any language.
The Protoss being a telepathic race, get around this.
The explanation was particularly elegant in that the Babel Fish is said to survive by "eating" unconscious thoughts and emotions from thinking beings around it, and the means by which it "processes" these thoughts leaves only the most superficial surface thoughts — i.e. the thoughts behind intentional, verbal communication — "undigested" and excreted into the host's mind. In other words, it's an explanation for why it's a perfect translator and only a translator. Whereas other times, when the Universal Translator works by some kind of telepathy, it leaves open the question of why you can't use it to tell you what the guy is thinking all the time rather than only when he's talking to you.
Additionally within The Hitchhiker's Guide to the Galaxy series, some words and phrases have almost universal phonetic equivalents in every other language, even though the meanings often vary considerably. There is, in any society advanced enough to make mixed drinks, a drink that sounds like 'gin and tonic', for instance, and throughout the known universe, our planet is the only one which uses 'Belgium' to mean something other than the most extreme profanity.
We're also shunned for using the word 'cricket' to refer to a ball game, as the rest of the galaxy still remembers the Krikkit Wars. The equipment used to play cricket on Earth strongly resembles the Earth-Shattering Kaboom-scale weaponry used in said wars, which is considered by other races to be extremely tactless of us.
Additionally, there are phrases such as "I seem to be having this tremendous difficulty with my lifestyle" that will occasionally fall through a rip in time-space, and starting an intergalactic war because of its interpretation as a huge threat/insult at an alien conference table.
They were really tiny; they'd never have been able to put Babel fish in their ears.
In the publication of the radio transcripts, Douglas Adams revealed that the Babel Fish was in response to the fact that every alien in movies, TV and literature can speak perfect English. The reason: the Earth people they are talking with have Babel Fishes in their ear and we never knew.
C. S. Lewis averts the trope at the end of Out of the Silent Planet: the academic main character, who has lived with the alien planet's natives and learned some of their language, is recruited by a human Corrupt Corporate Executive to translate a speech full of flowery white-man's-burden rhetoric about why they should let him colonize their planet and take their resources. The main character does his best to render it within the grasp of his basic Alienese and ends up completely exposing the antagonist's agenda without twisting a single word. The main character is a Philologist, and it took him several weeks to come up with a basic understanding of the language. In addition, a bunch of the plot of the next two books hinges on the fact that the main character can now speak Alienese, which it turns out is the universal tongue of everything outside of Earth, including Martians, Venusians, and angels of heaven. This allows him to act as an agent for the interests of Heaven in a way that Satan and his minions never anticipated.
The Yeerks are apparently teaching* various hosts (Hork-Bajir especially) English so they can talk to each other. Their alternatives were Taxxon (good luck pronouncing it without a several-foot tongue), the Hork-Bajir or Gedd languages (too simple), or some other Earth language (pointless as most of their human hosts knew English already). On the whole though this isn't too improbable. Human-Controllers' Yeerks would know English from their hosts' memories, and Hork-Bajir speak a strange mix of Galard and English ("Stop that gafrash shooting, logafach."). Taxxon-speak is said to be almost impossible to decipher, even for Controllers.
The free Hork-Bajir likewise speak mostly (crude) English mixed with their native language, but their Seer (who has genius-level intelligence by human standards, even) speaks flawless English - leading a National Guard commander to remark about the "aliens speaking more perfect English than [his] troops." It is also revealed in "Visser" that Hork-Bajir brains actually mangle the different languages together naturally. Which means even when controlled by a Yeerk, the Yeerk will find themselves mixing the languages as well.
The Andalites are a telepathic species, so it's justified with them.
The mi-go in H.P. Lovecraft's The Whisperer in Darkness speak English, but that's because they've been on Earth in secret long enough to learn our languages. And it's mentioned that they need surgical help in order to even produce the sounds necessary for human speech. They communicate with each other by telepathy, as well as bioluminescent colour shifts. They speak by buzzing, which sounds creepy and abnormal even though they can technically get the English sounds just right.
S.P. Meek apparently thought this was too absurd a trope to use in his story Awlo of Ulm. Instead, his miniature Serkis Folk spoke Hawaiian. For no apparent reason and without so much as being lampshaded. If you think that's bad, but keep reading anyways, you're in for a time...
In the short story "On a Clear Day You Can See All the Way to Conspiracy" by Desmond Warzel, the aliens speak perfect English; for at least two of them, however, this is justified, as they've been hiding out in suburban Cleveland and would need to speak English to blend in.
Lampshaded in a The Adventures of Samurai Cat tale. The duo are on an alien ship trying to decipher the controls, and find that they're actually labelled in Japanese. Then they realise that, despite being from 17th century Japan, they were speaking English.
In Christopher Stasheff's A Wizard in Rhyme series, the Ordinary High-School Student protagonist transports himself to the story's alternate universe by deciphering a Summon Magic spell. The problem is, said alternate universe is a Fantasy Counterpart Version of Medieval Europe, and he explicitly learned their version of French. Then he goes and has adventures with Italians, Germans/Austrians, even Muslims, and yet there is no language barrier. French actually was a widely-used international language for quite a bit of the middle ages. Several of the people he meets are visibly uncomfortable with it as a second language (especially the Arabs), and he occasionally has to fall back on magical translation.
In the H. Beam Piper short story Omnilingual, a female archaeologist faces the skepticism of her colleagues when she tries to translate the long dead language of Martian, despite the fact that there could be no possible 'Rosetta Stone' (a message with a known language paired with the same message in the unknown language). She finds it anyway when they come across the Periodic Table of Elements in a Martian university.
Spoofed in Star Smashers of the Galaxy Rangers by Harry Harrison. Every alien race the heroes come across has “listened to your radio broadcasts” and learned fluent English for one reason or another.
In the Alice, Girl from the Future series, all the aliens speak Russian, as do fairy tale and fantasy creatures from different countries in The Time of Myths. This is never explained, although Pashka lampshades it in The End of Atlantis and presents a convoluted and obviously incorrect theory that the modern Russians are distant descendants of the Atlanteans. Alice calls him on it (However, this was before they learned these were aliens). Also, there is an intersellar Common Tongue (and Alice has no problem understanding a 25 centuries oldAlien Popsicle), Alice had to learn alien languages at least twice, and Space Pirates seem to have an all consonant language. Hypnotic means to quickly learn languages are mentioned. Such knowledge doesn't stick for long, but most space travellers still use it out of convenience.
The fairies in Artemis Fowl rarely interact with humans and only innately understand their own language(s), but they can speak/comprehend any human language perfectly, via magic (they call it the "gift of tongues"). This means that characters who lost their magic by breaking the rules have to learn human languages the usual way.
Zenna Henderson's "People" learn English by immersion, except they read your mind while you're talking, so they have an advantage when they mentally decode your words, then reverse the process when they want to talk. Some are better at it than others, and they can get really garbled when they're flustered. Eliada in "Tell Me A Story" actually comes across as a bit of a Funny Foreigner.
In Timothy Zahn's own-universe Conqueror's Pride, the alien species interact normally with humans, although the Yycromae speak in what appears to be a telepathic connection rather than conventional speech. The Zhirrzh, which capture Pheylan Cavanagh, have a struggle developing a medium through which to interrogate him and Pheylan sometimes wonders how to convey complicated human concepts, such as his physical need for sunlight, through their limited comprehension of English. Zahn has obviously thought about this trope and tried hard to avert it.
Isaac Asimov's The Gods Themselves works around averting this trope too, built around two parallel universes. A human-built energy pump is sucking energy from the other dimension in order to provide Earth with an supply of apparently free energy. The first third of the book revolves around the receipt of an alien message by a journalist, Lamont; he recruits Bronowski, a professor of archaeo-linguistics, to decipher the symbols. In the second part, we see the aliens' side of the exchange.
This work also has aliens mastering English through empathy
The souls from The Host can speak English, but only the ones who've got human hosts, and only because their host would have known it first (assuming that the host did speak English, of course. The story's set in America, though, so for our purposes it's a moot point).
In one story in the Callahans Crosstime Saloon series, one of the humans compliments an alien on how good his English is - only for the alien to respond drily that the language was invented by his direct ancestors.
People in dozens of different worlds in Spider Circus speak English. However it's justified because the circus travels to those worlds specifically so the performers can be understood. There's some explanation for why one language is spoken in so many different worlds but it's Metaphorgotten and we do get a quick glimpse into a world where Latin appears to be the main language.
Although the later incarnations of Star Trek make occasional mention of "Universal Translators" being built into the uniform commbadges, the Original Series simply ignored the question of language except in a few rare instances. The handwave doesn't explain the times where communication does become a problem, or where certain words get left in the original.
Some episodes of the Original Series do have justified uses due to previous contact with humans.
The issue of different words/inflections/etc came up in Star Trek: Deep Space Nine. When analyzing a conversation between Weyoun and Sisko about a peace treaty, they remove the automatic translation to discover a key point in his delivery that the English translation glosses over.
Not handwaved in Enterprise, because Hoshi was there to serve as a translator. The times she wasn't essential were usually when they met advanced species that likely had their own version of a universal translator.
An episode of The Outer Limits has aliens approaching Earth. They send a video transmission with garbled language. Tension grows and at the climax, the U.S. President decides to launch nuclear weapons at the aliens, to no effect. The aliens launch extremely directed weapons to kill just the U.S. and Soviet leaders, just as translators reveal the transmission was in English, but underwater (since 70% of the Earth is water). The message was the President's very campaign promise "We come in peace and brotherly understanding." The President says "At least the nation will survive," as the weapons hit.
Doctor Who managed to explain this one by having the Doctor being able to mentally translate for his companions, who rarely thought anything odd about the fact they understood them. One of the Doctor's earlier companions did ask him once, but they were interrupted before he could answer and it was never brought up again. In the revival of the show that began in 2005, the translation is mentioned on more than one occasion to be performed by the Doctor's vehicle, the TARDIS, which is telepathically linked to the Doctor to the point that when he is unconscious, the translation fails. This became a plot point in the 2005 Christmas special, where an alien speech slowly turns into understandable English, indicating that the Doctor is back in action and ready to deliver the smackdown.
It often plays the trope straight, however, when aliens invade Earth. The series four finale features Daleks that speak (bad) German when they invade Germany. Exterminieren! Exterminieren!
Parodied in "Rose", where Rose isn't so much phased by the Doctor speaking English, but by his very distinct Northern accent.
Rose: If you're an alien, how come you sound like you're from the North? Doctor: (defensively) Lots of planets have a North!
At one point in the original series, it's stated that the translation is supposed to be unnoticeable. The fact that Sarah Jane Smith stops to wonder why she can understand Italian is evidence to the Doctor that something is wrong.
The 456 in Torchwood: Children of Earth speak actual English through all of Earth's children, even in places like Taiwan. The characters make note of it and it has a certain significance. Along with the hour at which they choose to speak, it indicates that the 456 are addressing Great Britain, with which they've already had secret dealings.
Stargate SG-1 has aliens, diaspora humans, and beings from other galaxies speak English. The issue of learning the local language served as something of padding in the movie on which the series is based, so this might actually be a case of Translation Convention, since the team members can be reasonably expected to be familiar with the common galactic languages (especially as most of them are dialects of Coptic or Latin). It was lampshaded in the novelization of the pilot episode "Children of the Gods", but that was more of Oneshot Revisionism.
Now try explaining that when the Goa'uld haven't been a major power on Earth since ~3,000 BC.
Becomes particularly egregious in Stargate Atlantis, when they go on their very first off-world mission without a linguist, and suddenly everyone turns out to speak English there too. And most that includes the holograms and flashbacks of the Ancients - yes, the very same Ancients whose specific not-even-remotely-English language has been heard and seen written down all across the span of the previous series.
Especially noticeable with the characters of Teyla and Ronon Dex, as while both are "human", they both come from other planets in other galaxies and yet apparently can speak and understand English without any problem.
Worse yet, the Tau'ri (as the humans of Earth are called) are practically the only humans in the universe exhibiting multiple languages - it's harder to understand the Russians than the humans from another galaxy who didn't even have ancestors on Earth!
Mostly averted thus far in Stargate Universe. The entire ship, control panels and all, is nothing but Ancient writing, and the one alien species they've come across thus far is apparently incapable of speaking English. Said species can still write English, but that's justified since they Mind Probed Rush beforehand and probably got the basics.
The movie that started it all, Stargate, included the process of establishing communication with the locals, with all the slow laboriousness such as would not have worked as a regular feature of any TV show. (So did the SG-1 Season 4 episode "The First Ones," with an aboriginal alien, portrayed as Other enough not to know English.)
Openly lampshaded in the "Wormhole X-Treme!" episode. Two of the crew get into an argument over whether they should have the off-world food be alien in appearance. When one demands whether the viewers will willingly suspend their disbelief in seeing a normal apple on an alien world, the other retorts it's not half-as-bad as all of the aliens speaking English.
Crusade, the short-lived sequel series to Babylon 5, played with this trope in its homage episode to The X-Files, "Visitors From Down The Street". After rescuing a pair of aliens of a previously-unknown race who unexpectedly speak English, the Excalibur is hailed by an alien ship — again in English. Captain Gideon comments sarcastically that either they're the same race as the others, or there's a busy English teacher running around that part of the galaxy.
In the miniseries (and series) V, this is justified in that, since the aliens are trying to indoctrinate themselves into human culture, they must speak the local language at all times. Including poor Willie, who was meant to go to the Middle East and thus had learned Arabic, but ended up in the U.S. due to a bureaucratic bungle and was forced to stumble through English on short notice. The 2009 reboot solves this problem in two ways. First it shows the Visitors using some sort of universal translator, as in their introduction when their leader Anna's address is seen being broadcast across the entire planet and can be audibly heard in the local language of wherever its being seen. Also, Visitor sleeper agents have been living on Earth for decades prior to the arrival of Anna's fleet in order to gather intelligence on humanity and learn Earth's languages in preparation for the arrival.
The various screen adaptations of Flash Gordon all feature the Mongonians speaking flawless English, with no explanation as to why. The 2007 serieslampshades it, but still doesn't explain. The novelization of the 1980s film explains that Ming, not wanting to waste countless hours teaching his prisoners the language, had the knowledge beamed into their brains while they were transported to Mongo.
As noted in David J. Schow's book on The Outer Limits, there's only one episode of the original series ("The Zanti Misfits") in which the aliens don't speak English, although various episodes justified this with different handwaves.
Farscape handwaves the issue with Translator Microbes. These enable characters from different cultures to understand each other with ease, including the human Crichton. Notably, some of Crichton's sayings (such as "fed up") don't translate properly, leading to some confusion. According to the series (though this is sometimes forgotten; see below), anyone that has translator microbes can understand anyone else - whether or not they have them. (In "Self-Inflicted Wounds", the crew encounter the Pathfinders, who have never made contact with the other species. The crew understands them perfectly, but before one of the Pathfinders is injected with translator microbes, none of them understand "the differing voices.")
In season 4, Aeryn actually tries to learn English in case they ever get back to Earth and makes some progress. There are also a couple instances where the others try to speak in human phrases, though it understandably proves difficult. When the crew actually do make it to Earth in "Terra Firma", some humans - including Crichton's family - understand them, suggesting or showing that they have gotten translator microbes to better talk to them.
It becomes a problem in "Constellation of Doubt," though, when the whole crew is shown to be speaking English in the TV documentary. The premise assumes that the entire viewing audience would have received translator microbes; otherwise the documentary should have been subtitled.
In "I, E.T.", the crew crashes on a planet that has never had interplanetary contact. Crichton is able to understand them (which works), but the inhabitants understand him (which shouldn't and isn't really explained).
Recurring character Sikozu, however, actually does speak English (or whichever language is necessary at the time). According to her, her species can't tolerate translator microbes, but can learn other languages if spoken to after sufficient time.
Averted in Kamen Rider Kuuga, where the Grongi monsters speak their own incomprehensible language.
The same happened in Kamen Rider Blade in which the majority of the Undead couldn't speak Japanese (or any other human language for that matter). Instead, they spoke in gibberish
Tokusou Sentai Dekaranger (and naturally its English counterpart Power Rangers S.P.D. as well) averts this for once by having one Alienizer who couldn't speak the local language without a translator device. The Alienizer was also a body switcher, switched bodies with the Blue Ranger and destroyed the translator device. So the Blue Ranger, in the body of a wanted criminal, had to prove to his friends that his own body was used by the criminal, while not being able to communicate normally. The majority of the other aliens speak perfect Japanese/English.
Actually not the first case of Alien speaking gibberish in power ranger. Remember Lunatick (From the power ranger in space ep where Zhane woke up ep.) He spoke an unknown alien language. and then there the Bookala (From season2), who more of learning english by repeating the word at first?
Almost lampshaded in Bakuryuu Sentai Abaranger: The Parasaurolopus Bakuryuu, having travelled from its native Dino-Earth to our Earth, ends up in South America and must swim to Japan where the others are. When he arrives he speaks perfect Japanese, but with the occasional "amigo" and the like thrown in for gags.
In Space: 1999, everybody in the universe speaks perfect English with no explanation. In this series NOTHING is ever explained.
Well... in one early episode the Alphans pass through a wormhole created by a "black sun" and encounter a god-like intelligence. It's conceivable that this entity gave them the ability to understand alien languages. On the other hand, it's probably unlikely that the writers would have even thought of that.
On 3rd Rock from the Sun, the aliens seem to be fluent in all Earth languages. In one episode, Harry turned on a Hispanic channel and all the Solomons started conversing in Spanish until they realized it wasn't the dominant language in Ohio. In another episode, Dick tested Tommy's intelligence by asking him questions in various languages.
Lost in Space "The Keeper", The Keeper speaks English, and explains that he has monitored their radio transmissions and has a limited form of telepathy to help him understand the language. It is odd that he would go out of the way to explain this, as the Robinsons didn't ask him how he could speak, probably because it wasn't the first time they encountered an English speaking alien without explanation.
The aliens who came to steal Jerry's milkshake machine in the Wizards of Waverly Place episode "Wizard for a Day" seem to have an excellent command of American English, lampshaded by the fact that they have no use for Justin and Zeke's "alien language".
With a case of demons speaking English, in Angel the inhabitants of the demon dimension Pylea speak English and communicate with dimensional travellers without problem, but their books are still written in strange demonic tongue that takes effort from a person familiar with the dialect to translate.
Speaking of 'Angel' - why on Earth is Illyria speaking perfect unaccented English? Considering that the creature lived when humans hadn't yet come into being or were little more than apes, one would expect it to have a real, REAL lot of trouble understanding any human language. One could assume that Illyria absorbed the knowledge of English automatically from its 'shell'. Still, it should have been given at least some time to process and learn to apply that knowledge.
You do realize the being you think needs time to master a relatively simple language is in fact the closest thing to a god that demons have, right? She can talk to plants, humans are hardly an effort for her.
In the pilot episode of Alf, Willie's radio intercepts ALF's spaceship and then ALF's voice comes out, but he appears to be speaking a different language. Then, when ALF is brought into the house, he not only speaks English, but he speaks English fluently, tells pop culture jokes and apparently, so do other Melmacians. Also, anytime that we see a book from Melmac, it is in English. How contradictory!
Xena travels to Rome, Brittania, Africa, India, China, and Japan, yet never runs into language barriers.
In Galactica 1980, the crew of the Galactica discusses a difference in languages, but Galactica 1980 and its predecessor Battlestar Galactica had characters speaking English with a few words and terms thrown in for flavor. However, the actors on the show did seem to have a problem with the word "starboard," putting the emphasis on "board."
Parodied in Hyperdrive, in which the aliens speak their own language that, by pure coincidence, is exactly the same as English.
In Lexx, no one ever had a problem understanding one another, even when they were from two different universes. This comes into question when the Lexx reaches Earth and Kai, the undead assassin wants to read a newspaper, so he asks a boy to start reading some of it for him. The boy says, "fifty cents," and Kai informs the boy that Kai can now read the rest without help.
Justified with Defiance's Votan population as they're trying to integrate into a mostly human society. Though they do often speak their own languages as well.
Possibly justified in 4E Dungeons & Dragons, by the shardminds. The reason they can speak any language is most likely that they access the creatures memories, copy the language, and speak with it. Frankly, it makes sense.
Feng Shui's GM section notes that just like in Hong Kong movies, everyone in the setting speaks perfect contemporary Cantonese, from Ancient Egyptian Pharaohs to the Prime Minister of Belgium to the bio-engineered abominations of the future — and in your games, everything's being translated into English, including the puns. Screw realism.
Played straight in pretty much every 40k video game, though.
In Rifts, most alien races on Earth were transported there by accident generations ago, and speak English note or American, as it's called in the main setting as their first language, making this a Justified Trope. Played wholly straight in the Three Galaxies setting, where the language Trade Four is so close to English that a Native English speaker can also speak Trade Four at about 50% proficiency. This is used as a hint that the Humans of the Three Galaxies come from some version of Earth.
In Perfect Dark, the player character Joanna Dark is accompanied several times by an alien. Called Elvis. Who wears a vest with the stars and stripes on it. On Elvis' first (conscious) appearance, Joanna exclaims "You... you speak our language!"
Elvis, as you can probably guess from the name, a big fan of Earth culture and he's also a soldier who was sent to Earth to aid the Carrington Institute so he'd need to know the language of its founder.
Shenmue II has Ryo Hazuki travelling to Hong Kong and China. Apparently everyone there speaks Japanese (or English in the dub), even Shenhua, who's from a remote village. The game was originally planned to use different languages but this idea was dropped long before release.
The alien species in Mass Effect have no problem speaking English to the various human characters they encounter. Then again, many of them also have other, non-verbal methods of communication, like the elcor, and others, like the asari, are very experienced at learning foreign languages and using biotic empathy to gain knowledge from other species.
In the Mass Effect novel, one of the characters mentions that he is learning to speak a galactic standard language. This language is what the aliens use when speaking to each other and that is why they all understand each other.
Likewise, in the actual game, one of the NPCs looses a stream of Techno Babble, to which Shepard can to respond "Would you care to repeat that in Galactic?"
According to the Bring Down The Sky expansion, everyone uses Translator Microbes if they can't speak each other's language - it's more polite and speaks well of your education and your willingness to avoid xenophobia.
These translators are not universal. They have to be constantly updated as new words or slang or grammatical conventions arise in known languages. It's explicitly mentioned that whenever a new species is encountered it's a huge pain in the ass to get even their most common language translated and sent all over Citadel space. There are people (most often hanar) who spend their entire lives updating translation databases.
Somehow these Translator Microbes are able to translate accents as well. (Remember the turian mechanic on Noveria with the Jersey shore accent?) Especially the quarians: Tali's accent is vaguely Eastern European, one of the Admirals' is Generic British, Kal'Reegar is Adam Baldwin...
In Mass Effect 2, if a female Commander Shepard romances Thane Krios, he will use a word that Shepard's translator is unable to understand, saying her "translator just glitched."
There's also a part in the original game where it's pretty clear that another human is speaking in Japanese, and Shepard's Translator Microbes are turning it into English for the commander's benefit.
And then there's the Shadow Broker, who knows and speaks at least 17 different languages (this figure is from when he was still Operative Kechlu) without using a translator, one of them possibly being English. Must have been fairly difficult, what with that mouth and all.
In Mass Effect 3, Javik is able to speak Galactic standard after merely touching Shepard. Explained as an inherent ability of the Protheans to absorb information and memories empathically and through touch, like their Beacons.
Which lends itself to a wonderful bit of brilliance, when one remembers that the first game revealed that Shepard had the Prothean language downloaded into their subconscious. In other words, Shepard's mind already contained a Prothean-to-English dictionary for Javik to learn from.
Most baffling of all, Liara's doctorate in the Lair of the Shadow Broker DLC is shown in English. The doctorate she earned on Thessia, the asari homeworld. While humanity were still "those funny hairless monkeys the turians just finished scrapping with".
In most of the Halo games, the Covenant's Grunts, Brutes, and Prophets all speak English. In Halo 2, even the previously unintelligible Elites start taunting the player in English. They even speak it when there are no humans around. Obviously Translation Convention in that case. In Halo: First Strike, this is explained as due to standardized UNSC translation technology. Halo Wars also states in the Timeline that large numbers of Covenant soldiers are taught to understand human languages. It's vaguely implied throughout the Expanded Universe that Grunts are especially adept at learning new languages despite being otherwise not all that intelligent which sort of justifies them speaking English.
Also referenced in Halo: Glasslands, which notes that the Elites, despite having four mandibles instead of a lower jaw, can approximate some human languages by moving their lower mandibles together like a jaw. Humans have a similarly tough time pronouncing Sangheili properly, though at least one human is shown as somewhat capable in the language. Neither are without faults, however: Elites cannot (or at least have extreme difficulty) pronouncing anything involving their non-existent lips, and one fluent human speaks like an "idiot child".
Averted by Halo: Reach. Every Covenant race only speaks their native language. This is lampshaded and parodied by a sleeping Grunt on "Nightfall" who says ""It's funny, but I dream in English".
The Forerunners and their AIs can also speak English, though this is explained as them having much more advanced translation capabilities than both humanity and the Covenant.
In Outcast, the hero finds himself thrust into an alien world on a Bronze Age - level. He has no trouble communicating with the natives, who also have their own language used when not communicating directly with said hero, and never stops to wonder at this, being more bothered re: aliens, the existence of, local evil empire, the overthrowing of. The player is encouraged to accept this as a necessary break from reality, until it turns out that there are no Translator Microbes - the aliens have all been speaking proper English. The hero meets a scientist from the same world-thrusting expedition, who lampshades the matter only to be told that the empire instituted the use of the shadowy Big Bad's language. Dun dun DUNNN!
Inconsistent in the Metroid series, or at least the games where Samus interacts with anyone. On the one hand, Space Pirates and Luminoth speak in unintelligible growls and so forth, and Chozo runes need to be translated. On the other, the three non-human Hunters in Metroid Prime 3 all have English voice-acting, and the Pirates are veritable chatterboxes in the manga. Prime 2 implies it's due to Samus carrying a universal translator.
Done rather oddly in the video game, Heart of Darkness. The cheerful Amigos can speak English, but it appears their primary language is actually Spanish.
Killzone's' Helghast speak English with a British accent while the Humans from the ISA speak it with an American one. Probably justified in that the Helghast are an offshoot species of humanity created when humans (likely from an Anglophone company or region) adapted to the planet. Lampshaded by the Big Bad's attempts at "language reform," which succeeds in changing the alphabet but eventually falls short of changing the spoken language due to "logistical difficulties."
All of the alien races in the Dawn of War games speak English. Normally, one would be able to pass this off as Translation Convention, except when humans and aliens (especially Orks, who probably wouldn't bother to learn any other race's language) talk to each other.
It's all Translation Convention. Even the Imperial forces aren't speaking English, they're speaking Low Gothic. The Latin bits are High Gothic, which are said to be effectively the same relationship to us as Latin/English today. That being, some similarities between Gothic and English, but not much you could really catch at first glance.
Inazuma Eleven 2 has plenty of aliens who all speak perfect Japanese. This later turns out to be because they're actually native Japanese humans under the influence of the Aliea meteorite's power.
Every alien race in Darkstar One speaks English. Word of God states that the reason behind this is because English was established as the standard spoken language in the galaxy.
The 4 main alien races in the X-Universe all speak Japanese. Translation Convention makes them all speak English or whatever language the user set the game to use.
In the first two Gothic games, only one orc is able to speak human language (and only because he was a human slave). In Gothic 3 all orcs suddenly are able to speak human language.
The Protoss are telepaths; presumably the (Terran) listener hears in whatever language they know. Note, however, that they do have a language of sorts, that can be both written and telepathically "vocalized".
The Zerg, being a hive-mind, has no need for language. Only the rare sentient Infested Terrans have been known to occasionally communicate with other species.
Draenei who had recently crashed on Azeroth and never encountered any of the local races still understand Common enough to communicate with humans, night elves, and dwarves before even leaving their starting zone.
Pandaren from the Wandering Isle seem to have no problems speaking both Common and Orcish when encountering the Alliance and Horde for the first time.
Every race from Pandaria apparently speaks fluent Common/Orcish (except [[Pardon My Klingon Hozen) despite the continent having been closed off from the rest of Azeroth for 10,000 years, presumably longer than said languages have existed.
In Sluggy Freelance, some aliens (like the ones who invade the North Pole) have their own language (represented in the strip by truly bizarre symbols in their speech balloons). However, the series also features Aylee, who was speaking English mere hours after first bursting out of someone's chest. Perhaps because she came from a dimension explicitly based on Sci Fi stereotypes, which this trope certainly qualifies as.
Last Res0rt wholeheartedly admits they speak English; specifically, they speak GET (Galactic English Terth), which is about as different from Modern English the same way there's a distinct difference between Biblical Hebrew and Modern Hebrew. However, in the same breath they admit GET is mostly a business/high-class language; part of the reason the show only does an hour a week of live broadcast is because translating and reformatting the program for so many different planets takes up so many resources that they can't afford to do them on the fly all the time. (The 'between shows' broadcasts are translated / parsed at relative leisure.)
All of the criminals featured so far can also speak GET, so it can't be too uncommon... then again, anyone who couldn't get past the interview process for being unable to speak the same language as everyone else wouldn't be on the show anyway.
According to Norman, aliens would probably speak with a slight French inflection. "We come in le peace!"
There are multiple galactic languages in Schlock Mercenary, but English still makes the short list. At one point mid battle a gatekeeper stops to correct a mercenary's English, and complains if humans are going to force this godawful trade language on other races they should at least be good at it. He gets Killed Mid-Sentence. It's not technically English—it's Galstandard West, which is the common galactic language corrupted by English. However, most English puns conveniently work in Galstandard West as well. This is shamelessly lampshaded both by the narrator and the author in his occasional rants.
In Freefall, Sam Starfall speaks English just fine, possibly learning it from the human scientists that discovered he had stowed away on their ship. (After all, he can't con somebody unles he can speak their language!)
Depends on the situation in The Cyantian Chronicles by the same author as Alien Dice. On their homeworld most Cyantians speak their native languages but at the Mars Academy everyone is required to speak English. There are also a couple Cyantians who were raised on earth and speak English as a first language, most notably Darrik who has a slight Cajun accent.
In another comic by the same author, two characters from the main series, Chatin and Cilke, are trapped on Earth and discovered by a linguist major, who discovers that they're speaking modified latin. It's revealed that all the antropomorphic animals are genetically engeneered from human slaves by ancient aliens some two thousand years prior. All Cyantian languages are descended from Latin
The trolls from Homestuck - who aren't just from another planet but a different universe entirely - have no problem speaking to the human protagonists. Handwaved in canon, though, since they were responsible for the creation of our universe and their influence can be seen in this and many other circumstantial similarities (for example, the troll players' names and sigils became our classical zodiac). It's not really a matter of "Trolls speaking English" so much as "Humans speaking Alternian".
Justified in El Goonish Shive, Uryuoms have the abilty to learn (or teach) any language by rubbing their antennae on a person's forehead (or presumably anywhere close to their brain) for about three seconds. They can only do this kind of thing with languages though.
Explained in Jix that the Ambis (the alien of the strip) has a device that can download languages into the user's mind. Their androids, on the other hand, can learn a language if they hear enough of it.
In The Accidental Space Spy, when the human character asks "How come all aliens are speaking English?", they explain that the someone hid mind control devices on a lot of planets, which gradually turn one of the planet's languages into Vricaltian. The culprit? The Vricaltian Tourist Agency. To make it easier for tourists.
On the planet in Verlore Geleentheid Afrikaans is evidently the dominant language (some English is spoken too). But considering it's somehow identical to South Africa in every way save for some of the technology and the fact that the inhabitants aren't human that is to be expected.
In Winters In Lavelle, all of the humans in Lavelle (so far) speak English. However, it's averted with the Gard, a species of (rather violent, it seems) half-deer men. They all speak Gardish, and the only one shown to be able to speak English so far is Xan- though his grasp on it is rathertenuous.
Lampshaded in an Awkward Zombie strip about Mass Effect. All of the advanced technology and mental powers in the setting are made possible by mass effect technology. How does everyone speak english? A wizard did it.
Tripp is able to understand the Amazons because of a translator device put in his ear.
Transformers always speak English, even the ones who aren't from Cybertron. There's no real reason why, nor is it ever commented on. There's no reason given why exceptions like Transformers without humanoid robots don't, either.
Subverted by the Junkions, who speak English, but do it in a way that makes little sense... They "Talk TV". meaning, in a nutshell, their dialogue is pieced together from fragments of various Earth broadcasts, resulting in lingual mash-ups such as "Don't look behind door number two, Monty! It's time to play "End of the Line," my valentine! Ge-ronny-doo-ron-ron-ronny-moooo!"
Teen Titans ALMOST avoids this one. In one episode, Starfire's ability to speak English is justified by the fact that her kind can instantly learn any language through "lip contact" with someone who speaks that language. But unfortunately, by that logic, all of her other people, who appear in a previous episode, must have snogged English-speaking humans as well.
In the comics, it's eventually revealed that Tamaraneans can learn languages through any kind of touch; Starfire just smooched Robin because she felt like it.
This raises other problems when you realize that, given the sheer amount of languages that Robin knows, he should never have to translate for her (as he does when speaking to Joey Wilson, who is mute and speaks a sign language), unless learning a sign language would require a form of hand contact with which the alien character is unfamiliar.
But Sign Language isn't a sound. Starfire can't learn to SPEAK it through touch/kissing, because it is not SPOKEN, It only makes use of the hands, not the mouth/voice.
Kim Possible has two aliens of the same race that can speak perfect English from the get-go. Not only that, they even speak English between each other, when there's no others around...
In Invader Zim, almost all alien species speak English. Not only does Zim speak perfect English to humans (granted, with his own weird twists) but already before Zim arrives on earth Dib overhears the Great Assigning of the Irken invaders and seems to have understood everything.
The Adventures of Jimmy Neutron: Boy Genius flaunts this trope magnificently. There is even the "Galactic Cable Network" pay-TV service, complete with over 9 billion television channels...all in English. Bizarrely, before they encounter the aliens associated with said network, Jimmy reads a tablet sent from space and makes a throwaway comment about translating from Aramaic.
This was parodied in an animated segment of Saturday Night Live. African humans encounter aliens, who must consult an English-Swahili dictionary to translate.
In Johnny Test, this is lampshaded when they meet a race of Vegan aliens and Johnny states that it's good that they speak English.
There have been three alien races on The Fairly Oddparents: the Yugopotamians, the Bodacians, and the Gigglepies. All three speak perfect English. In fact, Mark talks with Earth Surfer Dude slang, and the Gigglepies are a Rhymes on a Dime race.
In the eighties cartoon, upon meeting Miyamoto Usagi for the first time (brought over through a dimensional portal) Raphael points out, "He's not only from an alternate dimension, but also ancient Japan. So naturally, he speaks English."
In the 2003 series an alien arrives and while at first speak a foreign language, the collar she wears is activated to translate it into English.
An episode of The Tick had a very bizarre take on this: two alien races, each with a language consisting of one word: the Heys and the Whats. The Heys, incidentally, all looked exactly like Arthur, which led to him being captured and interrogated by a What who had learned to speak Hey:
Lampshaded on a Fantastic Four cartoon. The aliens spoke in their native tongue for awhile, then freeze framed as an animated Stan Lee came out and said "For the convenience of those who don't speak Alien, we'll have them speak English for the rest of the episode."
Whilst not aliens (although, the jury is out on the Olmecs), everyone in The Mysterious Cities of Gold speaks the same language (which you would assume is Spanish). Whilst it may be logical for some of the Native Tribes to have some people amongst them who had learned the Spanish Language by the time Esteban and co arrive in South America, it certainly doesn't explain why every little village girl, hidden tribe and TAO (who had been alone on an isolated island until meeting Esteban and Zia) could speak Spanish.
Hawkgirl and the Thanagarians all speak English by default. Even to each other. Translator Microbesmight cover that one, and it's not impossible that Hawkgirl may have taught some of the Leaguers a bit of Thanagarian. Especially Batman.
In the episode "War World", there are a million types of aliens, all speaking english with no difficulty understanding anyone else. Given the spacefaring cultures in the DCU are heavily influenced by races like the Guardians—who probably think Clarke's Third Law is redundant—it's entirely possible that translator technology is common among species that have any interstellar dealings at all.
Khalil: "The people there spoke a different language, but we'll just pretend they spoke English. Just like Star Trek."
Not only can WordGirl speak English, but she can speak it better than you.
Virtually everyone can understand each other in Futurama. Native Martians speak English, Omicronians speak English, Neutrals speak English, it goes on. This is lampshaded in the sixth season episode, "Mobius Dick", when the Planet Express crew travels to a foreign planet to pick up a statue, written in English.
Leela: "'It's' shouldn't have an apostrophe. This means and it is crew. What the hell's wrong with you?"
Alien: "It's a minor error, lady. I mean, we're space aliens. It's a miracle we can even speak English."
Leela: "The miracle is that I'm not kicking your ass! I insist you recarve the entire statue correctly."
The titular character of Muzzy In Gondoland is an alien speaking English in a cartoon that teaches English.
1973-74 Super Friends episodes "The Power Pirate", "Too Hot To Handle", "The Balloon People" and "The Watermen". The aliens in all of these episodes spoke perfect English with no explanation.
Sym-Bionic Titan, being inspired by 70's super robot cartoons, doesn't even try to justify the alien main characters speaking English, or even bring it up.
The Danger Mouse story arc "Close Encounters Of The Absurd Kind" has DM and Penfold abducted by a UFO for physical assessment. The head alien, Dr. Zok, speaks a garbled alien language which after activating his translator speaks our "rather primitive mode of speech."
D.M.: Primitive?! Look, when I get loose from here, you won't need a machine to translate things for you. A thump 'round the ear means the same in any language!
Justified in Green Lantern: The Animated Series as the Power Rings carrying a universal translator. This becomes a plot point in "Babel", since the rings are all drained the translators are off and none of the main characters can understand each other.
In Lilo & Stitch: The Series, Frenchfry, Jumba's 62nd experiment, speaks fluent French despite Jumba having never been to Earth until after Stitch was created.
Not going to happen in any first contact situation. We can't even manage decent machine translation of widely-spoken human languages; even with better translator tech, it would probably take years to perfect understanding of a completely new and unstudied language. And that's even if the aliens in question aren't so non-humanoid that they don't even use something analogous to human syntax and semantics. And that English is still in regular use in the far future.
A strange Earthly variant may be the Indo-European language family. Many European visitors to India during the Renaissance and the colonial era noticed an uncanny number of similarities between Sanskrit, Greek, and Latin that couldn't be dismissed as coincidence, despite the former having seemingly evolved thousands of miles away from the latter two. As the field of linguistics matured, so did the study of these similarities, and it is now believed that the languages of much of northern and central India and nearly all of Europe (save a few outliers, like Basque, Hungarian, and Finnish) are descended from a common root.