instruction: Is the next sentence syntactically and semantically acceptable?

Anne and Cathy met.
OPTIONS:
- unacceptable
- acceptable

response: acceptable

instruction: Is the next sentence syntactically and semantically acceptable?

Why haven't any books been returned?
OPTIONS:
- unacceptable
- acceptable

response: acceptable

instruction: Is the next sentence syntactically and semantically acceptable?

Mary sent Bill a book,.
OPTIONS:
- unacceptable
- acceptable

response: acceptable

instruction: Is the next sentence syntactically and semantically acceptable?

Mary sang for everyone who wanted to hear her.
OPTIONS:
- unacceptable
- acceptable

response:
acceptable