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".

Where did the policeman meet several young students?
acceptable

John seems know about the bananas.
unacceptable

It was this hat that Tom said Al thought you wanted me to make Jack put on.

acceptable