人教课标 高一 必修 3 Unit 1 段庆

Festivals around the world Unit 1 Festivals around the world

Grammar 情态动词用法

Modal verbs such as may, might, will, would, can, could, shall, should, and must are used for many purposes. Find the sentences in the reading passage that use modal verbs. 1 Most ancient festivals would celebrate the end of cold weather… 2 Sometimes celebrations would be held after hunters had caught animals.

3 At that time people would starve if food was difficult to find 4 …or to satisfy the ancestor, who might return either to help or to do harm. 5 For the Japanese festival Obon, people should go to clean graves… 6 …this will lead the ancestor back to earth.

7 It is now a children’s festival, when they can dress up and go… 8 …the children might play a trick on them. 9 Festivals can also be held to honour famous people. 10 Harvest and Thanksgiving festivals can be very happy events.

11 In European countries, people will usually decorate … and will get together… 12 Some people might win awards for their… 13 At the Spring Festival in China, people… may give children lucky money in red paper. 14 These carnivals might include parades, dancing in the streets…

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。 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。

只作情态动词的 can / could, may / might, ought to, must 可情态可实义的　 need, dare 可情态可助动词的 shall / should, will / would 相当于情态动词的 have to, used to

can和could： 1) can的主要用法是：   A. 表示体力或脑力的能力：   e.g. The girl can dance very well. B. 表示说话的推测、事物的可能性等: e.g. Can the news be true? C. 在口语中, can可以表示请求或允许: e.g. Can I sit here?

can表示“能够”时与短语be able to同义，但can只用于一般现在时或过去时，而后者可用于各种时态。另外，can表示个人有某种能力，而be able to表示某人通过努力、克服困难做成某事，相当于succeed in doing sth.；叙述过去事实时，最好用was / were able to，因为could只表示过去具有某种能力。

如： Can you understand the different kinds of English these people are using? Two years later, he was able to speak very good Chinese.

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: e.g. 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:

e.g. 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。 　e.g. They can’t have gone out because the light is still on.

以could或would提问时，不能再以could或would作答，而应该用can或will。如： — Could I borrow your dictionary? — Yes, of course you can.

may和might： may常用来表示： A. 表示请求、允许; 比 can 较为正式:    e.g. 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。

e.g. -- I believe the man is from England. -- But I may be wrong. The guest may arrive this 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？

C. 表示祝愿; 但语气较正式: e.g. 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。 e.g. She said that he might take her bike. 她说他可以拿她的自行车去用。

除了在间接引语中以外，might 一般不表示过去的可能或者许可。如要表示过去的可能可以用could, 表示过去的许可可以用was (were) allowed to 或者had permission to。 表示现在的可能，其可能性要比may 小。

e.g. She might go home tomorrow. 说不定他明天会回家。 表示现在的许可, 语气比may较委婉, 一般用于疑问句(包括间接疑问句), 不可 用于肯定句或者否定句。 e.g. Might I have a word with you? 我可以和你说句话吗？

will 和 would： 1. will是助动词或是情态动词？ e.g. I will tell you something important. 我要告诉你一些重要的事。 （助动词） 

Will you tell her that I’m here? 请您告诉她说我在这儿，好吗？ （情态动词）   2. 在疑问句中用于第二人称，提出请求 或询问。 e.g. If you want help - let me know, will you? 如果你需要帮助, 让我知道, 好吗?

Will you type this, please? 请打印这个, 好吗？   Won’t you sit down? 请坐下, 好吗？ 3. would比will客气委婉。 e.g. Would you help us, please? 请您帮助我们，好吗？ （表请求）

I’d go there with you. 我要和你一块到那儿去。  Teacher wouldn’t allow it. 老师不会允许这件事。 （表意愿） （表许可）

shall和should： 1. shall用于构成将来时是助动词。 shall用于征求对方的意见，表示 “决心”是情态动词。 e.g. Perhaps I shall pay a visit to England this winter. 可能今年冬天我会去英国观光。 （构成一般将来时, 助动词）

Shall we go by train, Mom? 妈妈，我们乘火车去好吗？ （用于征求对方的意见，情态动词） I shall go at once. 我必须立即去。 （表“决心”，情态动词）

shall可以用于第一、三人称的疑问句，表示征求意见或许可；还可用于第二、三人称的陈述句中，表示允诺、警告、命令或威胁等。 e.g. You shall be punished if you break the rule.

2. should 表示义务、建议、劝告，意为 “应该”。 “should + have + 过去分词” 表示本应该在过去做但没有做。 e.g. You should keep your promise. 你应该遵守诺言。 She should have passed the exam. 她应该通过考试的。

must 和 have to 1. must用于一般问句中, 肯定回答用must 否定式用needn’t 或don’t have to，做 “不必”, mustn’t表示“禁止，不允许”  — Must I finish all assignments at a time?   — Yes, you must. /No, you needn’t.

2. 表示“必须”这个意思时，must和. have to稍有区别。must着重说明主观. 看法，have to强调客观需要。另外， 2. 表示“必须”这个意思时，must和 have to稍有区别。must着重说明主观 看法，have to强调客观需要。另外， have to能用于更多时态。 e.g. I don’t like this TV set. We must buy a new one. There was no more bus. They had to walk home.

3. must表示对某人某事的猜测, 作“准. 是”, “一定” , 一般用于肯定句中。对过. 去发生的事情作肯定判断用must have 3. must表示对某人某事的猜测, 作“准 是”, “一定” , 一般用于肯定句中。对过 去发生的事情作肯定判断用must have done。 e.g. You must be the new teacher.   He must be joking. There is nobody here. They  must have all gone home.

4. must表示“偏要, 硬要”, 指做令人不 快的事情。 e.g. He must come and worry her with question, just when she was busy cooking the dinner. Of course, after I gave her my advice, she must go and do the opposite.

can / could, may / might, should 和 must都可表示肯定的推测。can / could表示客观可能性；may表示推测时，其语气不肯定；might语气更弱，表示某事实际发生的可能性；should 表示确定或可能有的未来或期待；must表示比较肯定的语气。如：

I think advertisements can be quite dangerous. The newcomer may be dismissed by the company. The rescue team should arrive by 5 o’clock this afternoon. I think the old woman must be a nice person.

could, might, would, should 都可表示委婉语气。如: I wonder if you could let me use your cell phone. Might I know your telephone number?

高考链接 从A、B、C、D四个选项中，选出可以填入空白处的最佳选项。 1. — Shall I inform him of the change of the schedule right now? — I am afraid you _____, in case he comes late for the meeting. (福建 2011) will B. must C. may D. can B

2. — No one _____ be compared with Yao Ming in playing basketball. — Oh, you are really his big fan. (湖南 2011) A. can B. need C. must D. might 3. It _____ be the postman at the door. It’s only six o’clock. (江西 2011) A. mustn’t B. can’t C. won’t D. needn’t A B

4. — Will you read me a story, Mummy? — OK. You _____ have one if you go to bed as soon as possible. (陕西 2011) A. might B. must C. could D. shall 5. If you _____ smoke, please go outside. (2011大纲全国卷) A. can B. should C. must D. may D C

6. The police still haven’t found the lost 6. The police still haven’t found the lost child, but they’re doing all they _____. (四川 2011) can B. may C. must D. should 7. — Why didn’t you come to Simon’s party last night? — I wanted to, but my mom simply _____ not let me out so late at night. (重庆 2011) could B. might C. would D. should A C

8. Just be patient. You _____ expect the world to change so soon. (2010课标全国卷) A. can’t B. needn’t C. may not D. will not 9. — I haven’t got the reference book yet, but I’ll have a test on the subject next month. — Don’t worry. You _____ have it by Friday. (江苏2010) could B. shall C. must D. may A B

10. Doctors say that exercise is important 10. Doctors say that exercise is important for health, but it _____ be regular exercise. (辽宁2010) A. can B. will C. must D. may 11.“You _____ have a wrong number,” she said. “There’s no one of that name here.” (浙江2010) A. need B. can C. must D. would C C

12. — _____ I take the book out? — I’m afraid not. (四川2010) Will B. May C. Must D. Need 13. The traffic is heavy these days. I _____ arrive a bit late, so could you save me a place? (辽宁2009) can B. must C. need D. might B D

14. One of the few things you _____ say 14. One of the few things you _____ say about English people with certainty is that they talk a lot about the weather. (北京2009) need B. must C. should D. can 15. What do you mean, there are only ten tickets? There _____ be twelve. (2009全国卷I) should B. would C. will D. shall D A

Homework Finish Using Structures on Page 43 of Workbook.

Thank you!