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: They can sing.

A: acceptable
****
Q: I've never seen the one taller man than my father.

A: unacceptable
****
Q: They said nobody would pay up, but I know a boy who did pay up.

A:
acceptable
****