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".

Q: When can we register for graduation?

A: acceptable
****
Q: John is prouder of having gone than John didn't expect me to believe he would be.

A: unacceptable
****
Q: John asks which book by his father he read.

A:
acceptable
****