[典例剖析] 单项选择。
()1. —Stop! Sir，you look at your phone while riding. It's too dangerous.
—Sorry，I won't do that.
A.must
B.can
C.needn't
D.mustn't

1. D

1. 本题考查情态动词的词义辨析。A. must（必须）；B. can（能，可以）；C. needn't（不必）；D. mustn't（禁止，不许）。根据对话中“骑车时看手机太危险”的语境，可知此处是禁止骑车时看手机的行为，应选mustn't。
2. 本题考查情态动词的用法。第一空是孩子向妈妈请求许可“能不能看电视”，应用Can；第二空根据“太晚了”的语境，可知是要求“必须上床睡觉”，应用must，所以选对应的选项。

()2. —I finished my homework. I watch TV for a while，Mum?
—No. It's too late. You go to bed now.
A.Can；can
B.Must；can
C.Can；must
D.Must；must

2. C

[反馈练习](一)选词填空。
1. The light is red. We(should/mustn't)cross the road now.
2. The water in the stream is dirty. You(can/can't)drink the water.
3. The light in her room is still on. She(must/can)be at home now.
4.—(Must/Can)Liu Tao ride bikes?
—Yes，he(must/can).
5. Paul has a fever and coughs a lot. He(can/should)go to hospital at once.
6. Here's the green man. We(can/must)cross the road.

（一）1. mustn't 2. can't 3. must 4. Can, can 5. should 6. can

（一）1. mustn't 2. can't 3. must 4. Can, can 5. should 6. can

(二)按要求完成下列各题。
1. 你不应该以这样的方式把消息告诉她。(根据中文提示完成句子)
You her the news in this way.
2. People could go to work by ship every day.(对画线部分提问)
people to work every day?
3. He need drive me home.(改为一般疑问句)
he home?
4. You cannot draw picturesonthe wall.(对画线部分提问)
we on the wall?
5. —Must I be there by eight in the morning?(作否定回答)
—，you .
6.— on the road?(根据答句写问句)
—I must look at the traffic lights.

（二）1. shouldn't tell 2. How could, go 3. Need, drive you 4. What can, not do 5. No, needn't 6. What must you do

（二）1. shouldn't tell 2. How could, go 3. Need, drive you 4. What can, not do 5. No, needn't 6. What must you do