You're given a sentence and your task is to classify whether the sentence is acceptable or not. Any sentence which is grammatically correct, has a naturalistic text, is written by a native speaker and which minimizes superfluous content is acceptable, otherwise unacceptable. If the sentence is acceptable then write "acceptable", otherwise "unacceptable".

Which bed did Tom sleep on?
acceptable

Who do you think that Mary said that John likes?
acceptable

A man came into the room that no one knew.

acceptable