1. 选择合适的句子补全对话。

A. All right. B. Let's go to the shop. C. Stop and wait. D. Be careful. E. It's yellow.

1. （1） A: I'm going to buy a gift for my mother.

   B: OK.

3. （2） Look at the traffic lights.
5. （3） A: Don't cross the street.

   B: