人教课标高一必修 3 Unit 1

人教课标 高一必修 3 Unit 1

Unit 1 Festivals around the world Grammar 情态动词用法

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

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和could：

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’thave 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：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 guestmayarrive 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. Mayyou succeed! Mayyou 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。

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, 和may一样，表示现在的可能，但是可能性要比may 小。如： She might go home tomorrow. 说不定他明天会回家。

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。如: Might I have a word with you? 我可以和你说句话吗？

will 和 would： 1. will既是助动词又是情态动词 will用于构成将来时是助动词。用于表示“决心”“请求”“习惯” “请求和允许”是情态动词。would同理。 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？ I’d go there with you. 我要和你一块到那儿去。（表请求）（表决心）

Every morning, he will go out to do some morning exercise. （表习惯）

shall和should： 1. shall 用于构成将来时是助动词,相当于will 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。如： You shall be punished if you break the rule. If you do a good job in the coming exam, you shall get a big prize . Everyone shall obey the law.

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， have to 能用于更多时态。 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 done。 Youmust be the new teacher. He must be joking. There is nobody here. They must have all gonehome.

4. must表示“偏要, 硬要”, 指做令人不快的事情。 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 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 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 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

Find the sentences containing modal verbs in the reading passage. • Then usually by lunchtime they would all be sold. • What could have happened? • Nothing could be better … • Something terrible must have happened if …

He could not believe his eyes. • Perhaps he should go to the library and find out. • He had better do some research! • Even though her customers might get thin after eating Yong Hui’s food … • They would become tired very quickly.

a. should, ought to 都可表示“应该”。ought to 用于表示按道理应当，常指客观的义务或责任，大多数情况下可用should 代替，但比 should 语气重。 Modal verbs I should help her because she is in trouble. You ought to take care of the baby.

b. 表示劝告、建议或命令时，should 和ought to 可通用，但在疑问句中常用should。ought to 的否定式为 oughtn’t to 或 ought not to。 You should / ought to go to class right away. Should I open the window? What should we do next?

c. should, ought to 都可表示推测。 He ought to / should be home by now. This is where the oil ought to / should be. 注意 should 和 ought to 后面跟动词不定式的完成式, 其肯定句表示“过去应该做而未做”, 其否定句则表示“过去不该做但做了”。

You should / ought to have made the decision a week ago. I shouldn’t have made such a foolish mistake. 多数情况下，ought to 可与 should 互换使用。ought to 的反意疑问句用shouldn’t 替代。

You ought to have helped him with his English, ________? A. won’t you B. ought not you C. shouldn’t you D. wouldn’t you

2. must 和 have to must 的用法表示主观的义务和必要, 主要用于肯定句和疑问句, 意思为“必须……，；由 must 引起的疑问句，肯定回答要用 must 或 have to 必须否定回答要用needn’t don’t have to 不必

must 的否定形式 mustn’t 表示禁止，意思是“不能，不许”。如： —Must I finish the task right now? 我现在必须完成这个工作吗？ — Yes, you must. / Yes, you have to. 是的。 (— No, you needn’t. / No, you don’t have to. 不，不必。)

You mustn’t come here without permission. 未经允许，你不能来这儿。（禁止）　　 have to 的用法 1) must 表示一种主观的需要，而 have to 表示一种客观的需要，意思是“不得不”。如： I have to attend an important meeting this afternoon. 今天下午我不得不参加一个重要的会议。

Mother is out, so I have to look after the shop. 妈妈不在家，因此我不得不照看商店。 2) have to 的否定形式是 don’t have to, 相当于 needn’t。如： They don’t have to buy a computer at present. 他们目前没有必要买电脑。

人教课标高一必修 3 Unit 1