（ ）6. A. It must be Helen’s B. Yes, I find it. C. Helen has a pencil.
（ ）7. A. He is at home. B. He is at work. C. His back hurts.
（ ）8. A. No, thanks B. Certainly. C. I don’t think so
（ ）9. A. Never mind B. Sorry, I won’t. C. You’re welcome.
（ ）10. A. It’s full of mystery. B. I like it. C. Very much.
