instruction: Is the next sentence syntactically and semantically acceptable?

No spy betrayed himself.

response: acceptable


instruction: Is the next sentence syntactically and semantically acceptable?

John ate a carrot and Mary did so a radish.

response: unacceptable


instruction: Is the next sentence syntactically and semantically acceptable?

A man to be in the garden is unlikely.

response: unacceptable


instruction: Is the next sentence syntactically and semantically acceptable?

How do you think that Mary solved the problem?

response:
acceptable