Homer: How is it that you speak English?
Alien: Actually, we're speaking Rigellian. By coincidence, our languages are exactly the same.
To make things easier, everyone speaks English.
— A short story about humans meeting aliens. In Portuguese.
Graeme: How come I can understand you? Are you using some neural language router?
Paul: Actually, I'm speaking English you fucking idiot!
Farnsworth: Our only hope is to communicate with the aliens, and show them our peaceful intentions.
Bender: Perhaps they speak perfect English... as do we.
Farnsworth: We can't take that chance! We'll need my universal auto-translator!
The humans are having a dick-waving competition with various aliens that all speak perfect English, in various American dialects.
Letter: Dear Stargate SG-1, why do all the aliens speak English?
Christopher Judge: Oh Crap, they found out about that.
Chel: Hmm... How do you speak English so well?
Lexx: I'm not speaking English. You're speaking Galactic Standard.