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".

The two boys looked up the high stairs.
acceptable

I didn't eat any ice cream or any cake.
acceptable

We persuaded them to examine them.

unacceptable