instruction: Is the next sentence syntactically and semantically acceptable?

John hummed, and Mary sang, the same tune.

response: acceptable

instruction: Is the next sentence syntactically and semantically acceptable?

Nora pushed the chair against the wall.

response: acceptable

instruction: Is the next sentence syntactically and semantically acceptable?

John is prouder of having gone than John expected me to believe that he wasn't.

response: unacceptable

instruction: Is the next sentence syntactically and semantically acceptable?

No one can forgive you that comment.

response:
acceptable