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".

To behave oneself in public is expected.
acceptable

Penny rowed across the lake.
acceptable

Did you believe him to ever have made an effort to talk to the student?

acceptable