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".

John hit the stone against the wall.
acceptable

Robert thinks that student should eat asparagus.
acceptable

We expect the dentist to examine ourselves.

unacceptable