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".

I doubt you can help me in understanding this.
acceptable

How do you wonder which problem to solve?
unacceptable

Paula hit at the fence with the stick.

acceptable