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".

Ex Input:
Willy is taller than that Bill is is generally believed.

Ex Output:
unacceptable


Ex Input:
I insist on seeing through all the students who had started out the term in my class.

Ex Output:
unacceptable


Ex Input:
There exist few solutions which are cost-effective.

Ex Output:

acceptable