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".

Example Input: When can we register for graduation?
Example Output: acceptable

Example Input: Bill understands Mary and himself.
Example Output: unacceptable

Example Input: That new handle detaches from the box easily.
Example Output:
unacceptable