（ ）1. A . Yes, I did. B. Yes, I have. C. No, I don’t.
( ) 2. A. Not at all. B. Good idea. C. It’s wonderful.
（ ）3. A. It's wonderful. B. It’s dirty. C. It’s cleaner than before.
（ ）4. A. I have studied it for half a year. B. I’m doing well in it.
C. I have studied it very hard.
（ ）5. A. Cut down trees. B. Reduce the waste we produce.
C. Throw the rubbish away.
（ ）6. A. I agree with you. B. I hope so. C. I can’t decide.
