21．---I don’t believe smoking can damage your health as long as you exercise regularly.
---______!Years of medical research show smoking is a stupid and expensive way to ruin your health.
A. Nonsense B. You bet C. Sounds good D. Cheers
22. ---Why did you come by taxi?
---My car broke down last week and I still it repaired.
A．didn’t have B．hadn’t had C．haven’t had D．won’t have
