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".

Stephen believed the cat to be out of the bag.
acceptable

Mary's happy with her work, and John's with his children.
acceptable

Crystal vases break easily.

acceptable