instruction: Is the next sentence syntactically and semantically acceptable?

That you will marry any particular student is not certain.

response: acceptable

instruction: Is the next sentence syntactically and semantically acceptable?

Heidi saw drawings of her.

response: acceptable

instruction: Is the next sentence syntactically and semantically acceptable?

I have half a dozen of these marbles too many.

response: unacceptable

instruction: Is the next sentence syntactically and semantically acceptable?

These are the things for which to be thankful.

response:
acceptable