新课标人教版英语必修三Unit1语法课课件

4. He might have read about the news in the newspaper. 他可能已经从报纸上知道这个消息了。
5. You should have told him a week ago. 你本来应该在一周前告诉他的。
6. Can you give me some suggestions? 你能给我一些建议吗？
C. 表示祝愿; 但语气较正式: eg. May you succeed! May you have a good journey!
might 的用法有: 多在间接引语中表示过去的可能和允 许。如: She said that he might take her bike. 她说他可以拿她的自行车去用。
eg. Can I sit here?
2. could的主要用法是： A. could 是can的过去式, 表示与过去 有关的能力和推测: eg. We all knew that the young man couldn’t be a doctor. B. could可以代替can表示请求, 但语 气较can客气、委婉:
to……………………….=…must… is able to…speak English…
=…can… is allowed
to……………....=…may…
情态动词的语法特征
1. 情态动词不能单独做谓语，除ought 和have外，后面只能接不带to的不定式。
2. 情态动词没有人称，数的变化，但有 些情态动词，如can, will也有一般式 和过去式的变化。
meaning or an idea. Some common uses of the modals are these: Ability: 1 He can speak English now.
2 He couldn’t speak English a year ago.
3 I’m not able to come to the
下面我们具体了解一下几 个常用情态动词的用法。
can和could
1. can的主要用法是： A. 表示体力或脑力的能力：
eg. The girl can dance very well. B. 表示说话者的推测﹑事物的可能性:
eg. Can the news be true? C. 在口语中, can可以表示请求或允许：
7. They wanted to know when you would go to the park. 他们想知道你们什么时候去公园。
什么是情态动词？ (Modal Verbs)
情态动词表示说话人的某种 感情或语气，对某一动作 或状态的某种态度。 表示“需要、可以、 必须、应当”等。
Words like can, will, may, must, and a few others are called modals. Modal verbs help other verbs express a
eg. Could you lend me your dictionary? Could I use your bike?
3. can和could接动词的完成形式，表 示可能已经做某事。can用在否定和疑 问句中, 表示不相信、怀疑等态度。 eg. They can't have gone out because
Unit 1 Grammar
Modal Verb I
1. He must have gone to Beijing. 他一定已经去北京了。
2. The door was locked. She couldn’t have been at home. 门是锁着的， 所以她不可能在家。
3. They may be still waiting for us. 他们可能还在等我们呢。
the light is still on.
may和might
may 常用来表示： A. 表示请求、允许：
比can较为正式:
eg. May I come in?
You may go now. B. 表示说话人的猜测: “也许” “可 能”: 通常只用于肯定句和否定句中。
eg. — I believe the man is from England. — But I may be wrong. The guest may arrive this
Permission: All passengers may now board. We can board now.
Obligation: You must fasten your seat belts. (strong) You should pay attention. (weak) You ought to pay attention.
只作情态动词的
can/could, may/might, ought to, must 可情态可实义的 need,ห้องสมุดไป่ตู้dare/dared 可情态可助动词的 shall/should, will/would 相当于情态动词的 have to, used to
3. 情态动词的“时态”形式并不是时间区别 的主要标志，不少情况下，情态动词的 现在式形式和过去式形式都可用来表示 现在时间、过去时间和将来时间。
afternoon. 在肯定句中，may 的可能性比can 高， may 表示现实的可能性，can 表示理论 上的可能性。如：
The road may be blocked. 这条路可能不通了。
The road can be blocked. 这条路可能会是不通的。 在疑问句中，表示可能性用can。 如：Where can he be? 他会在哪呢？
Possibility: 1 It may rain. 2 How could I forget an important thing like that?
Meanings similar to those of the modals can often be conveyed by real verb forms: He has