Arguably the most famous line from the iconic 1994 film Pulp Fiction. Ironically, the original line was not asked in response to someone speaking incorrect English, but asked by Samuel L. Jackson's character as a rhetorical question to whether or not a frightened man spoke English at all after the man repeatedly said "what?" to his questions.
"'What' aint no country I ever heard of! They speak English in 'what'?"
"English, motherfucker, do you speak it?"