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".

They can sing.
acceptable

I threw the ball to Mary, but she was looking at the birds flying overhead and didn't even notice.
acceptable

When Kim was in China, I was too.

acceptable