instruction: Is the next sentence syntactically and semantically acceptable?

Cynthia gobbled at the pizza .

response: unacceptable

instruction: Is the next sentence syntactically and semantically acceptable?

Lilly recounted a story to be remembered because Holly had recounted a story to be.

response: unacceptable

instruction: Is the next sentence syntactically and semantically acceptable?

Sarah smiled.

response: acceptable

instruction: Is the next sentence syntactically and semantically acceptable?

In English, the main verb agrees with the head element of the subject.

response:
acceptable