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 more contented the nurses began to believe that we were going to pretend to be, the more angry we grew at the doctors.
unacceptable

the book with a red cover of poems from Blackwell by Robert Burns takes a very long time to read.
unacceptable

Volunteers praise easily.

unacceptable