题目内容：

第一节 从方框中选出最佳选项完成下面的对话。

A: Hi, Bill. You were not at school yesterday.     1.

B: Oh, I fell off my bike on my way to school and hurt my leg.

A: I’m sorry to hear that.     2.

B: No, my father took me to the hospital.     3.

A: We should be more careful when we ride. In fact, we should never ride too fast.

B: You are right.     4.    If we break the rules, we may be in danger.

A: Let’s go to the traffic station to learn more rules.

B:     5.