instruction: Is the next sentence syntactically and semantically acceptable?

John met in the park a student.

response: unacceptable

instruction: Is the next sentence syntactically and semantically acceptable?

It tends to be warm in September.

response: acceptable

instruction: Is the next sentence syntactically and semantically acceptable?

This proved my hypothesis.

response: acceptable

instruction: Is the next sentence syntactically and semantically acceptable?

How do you think that Mary solved the problem?

response:
acceptable