instruction: Is the next sentence syntactically and semantically acceptable?

The man I think that chased Fido returned.
OPTIONS:
- unacceptable
- acceptable

response: unacceptable

instruction: Is the next sentence syntactically and semantically acceptable?

John is the kind of the fool that I told you about.
OPTIONS:
- unacceptable
- acceptable

response: acceptable

instruction: Is the next sentence syntactically and semantically acceptable?

This objection is main.
OPTIONS:
- unacceptable
- acceptable

response: unacceptable

instruction: Is the next sentence syntactically and semantically acceptable?

Who do you guess will be here?
OPTIONS:
- unacceptable
- acceptable

response:
acceptable