Grammar and usage(1): Modal verbs: general introduction课时教案

Module4 Unit2 Grammar and Culture Corner 情态动词

学习目标：

1. 了解情态动词各自的基本意义及用法，

2. 掌握情态动词表示推测的用法

重难点：情态动词表过去推测的用法；还要注意带有情态动词的反意疑问句的用法。

情态动词的特征：

1.本身有词义，但完全。因此不能独立作谓语，只能和动词原形一起构成谓语。

2.后接动词不定式一律不带to

3.不随人称和数的变化。

情态动词各自的基本意义及用法

表一、can 与could用法对比表

对比点

can

could 1、表“能力”

Can you lift this heavy box? I couldn’t understand what he said at all. 2、表“许可”

You can use a different material He said I could borrow his bike. instead. 3、“怀疑”

No, no, it can’t be true. We thought the story could not be true. What on earth can this mean? How could you be so careless? 1.

could代替

can，表示语气更为婉转。

Eg. Could I use your bike?

Yes, I can 2.

can (能够)=be able to(仅表能力时)，但be able to 表示一番努力后，才4、can与be able to 区别

能做得到，且有更多的时态。

He was a good swimmer, so he __________ swim to the river bank when the boat sank. A. could

B. might

C. shall

D. was able to

表二、may与

might用法对比表

对比点

may Might 1．表“询问”

May I …?(=Can I …?) Might I …?(=Could I…?)(但比用may 更客气) 2.表“允许”

You may take the boy there. He told me he might come .(might 与told相呼应) 3．表“可能”“或许”

She may nor like this place. I’m afraid he might not like this play.

注：

1.

May I…?的答语。

肯定：Yes, you may. 2.may可表示期望或祝愿

否定：No, you mustn’t 不行（语气强硬）

May you succeed ! No, you may not 或No, you’d better not. 3.may (might)用于目的状语The emperor gave them some gold in 从句中

order that they might begin their work at once. 表三、must与have to的用法对比表

对比点

must have to （主观看法）必须；没有过去（客观需要）不得不，有多种时态。1．表“必须”

式，可用于间接引语中。He It’s raining heavily, we can’t go now. told me I must do according to what he said. Must I …? Do you have to go today? 2.疑问句

Yes, you must.（一定）

Yes, we do. No, you needn’t./ you don’t 否定句：You don’t have to worry about have to.(不必) that.

表四、need与dare的用法对比表

对比点

need dare 1.情态动词+动词原形

He need not (needn’t)go. He dare not say so.

1）否定式

----Need we do it again? Dare she go out alone at night?

2）疑问式

---No, you needn’t do it again. How dare you say I’m unfair? If he dare do that, he’ll be punished.(条件句) I dare say.(固定用法) 2.行为动词+带to不定式

He needs to go. He dares to say.

1）肯定式

He doesn’t (does not)need to He does not(doesn’t)dare to say.

2）否定式

go. If you dare to jump into the water from

3）疑问式

Does he need to do it again? here, so dare I . No, he doesn’t need ot do it again. 3. did not need to do She didn’t need to attend the meeting yesterday, and she stayed with her 表示过去没有必要做

children.(她没有参加)

表五、should与ought to用法对比表

对比点

should ought to 1、表“应该”

表劝告、建议

表示“有责任有必要”做某事

You should listen to the You ought to finish your work 1

doctor’s advice. before you go home. We should learn from Zhang We ought to help each other. Hua

表示“非常可能”的事，可译

为“总应该”

2、表“估计”

They should get home by now. If we start to work right now, we ought to finish it before lunch.(午饭前应当能干完)

1）、should还可在虚拟语气中的使用

2). 注意：ought to的疑问式及否定式

注：

----Ought he to go?

----Yes, I think he ought to. No, he oughtn’t to.

否定式：ought not to a或oughtn’t to do(不说ought to not do) 反疑问句：oughtn’t ______?

表六、shall与will的用法对比表

shall Will 1.

征询对方意见或请求指示，用于第一、三1．

询问对方的意思或向对方提出要求：

人称：

Will you(please)…? Won’t you…? Shall I (we)…? Would you like to…?(用would替代will更客Shall he (she)…? 气) Where shall I (we)wait for you? ----Won’t you go and see the film?你不去看电影吗？---Yes, I think I will. 不，

我想去。

2. 表示说话人的“意愿”有“命令”“警告”表示“意志”“意愿”，用于各种人称：

“强制”“允诺”“决心”等，用于第二、三I won’t do anything you don’t like. 人称，要重读。

我不会做任何你不喜欢的事。

You shall do what I tell you ( to do). Would表示过去时间的“意志”“意愿”

我叫你干什么你就干什么。

Shylock would not take the money earlier. Everything shall be done to save the ship. 夏洛克先前是不肯要钱的。

一定要竭尽全力来拯救这艘船。

表七：used to与would用法对比表

used to would 1.表示过去的动作、状态，重在与现在情况的1.只表示过去动作的重复，有明确的时间状语

对比，不一定要有时间状语。

I would go to see my grandfather on Sunday I used to play cards a lot, but now I seldom when he was in the middle school. play. 2.would 后只接表动作的动词，不接表认识或My hometown is not what it used to be. 状态动词

He used to be nervous in the exam. 2.表示过去的习惯有时可互换：

When we were very young, we used to / would go skating every winter. 2.

表示过去的次数时，不能使用：

( √）We went to the Great Wall five times when we were young. (

X

) We used to go / would go to the Great Wall five times when we were young. 注：used to do的否定式：usedn’t to do 或didn’t use to do (usedn’t也可写作usen’t) 疑问式：

Did you use to do ?

Didn’t you use to do?

Used you to do?

Usedn’t you to do?

情态动词表推测

情态动词表推测的意义：

1、大多数情态动词（除表‘能力、许可、意志’外），都可以表示推测，其程度有差异。按其可能性程度的高低排列为：

Must

﹥will ﹥would ﹥ought to ﹥

should ﹥

can ﹥

could﹥

may ﹥

might

肯定

完全可能

很可能

可能

有可能

2.注意区分情态动词的否定的含义：

may not或许不、可能不

might not可能不

can’t 不可能

mustn’t不许、禁止

shouldn’t不应该

needn’t 不必

3.情态动词表推测具体运用：情态动词可以对现在、进行、过去推测

S主+情态动词+be+adj 对“性质”“特征”的推测

S主+情态动词+be+n 对“职业”“事物”的推测

S主+情态动词+V原

对经常性行为的推测

S主+情态动词+be+V-ing 对进行着的行为的推测

S主+情态动词+have+PP 对过去的行为的推测

特别提醒：情态动词表推测时

1、

can只能用于否定句和疑问句

2、

must只能用于肯定句（它的否定句和疑问句其实就用can来代替了）

3、

如句中有情态动词

+ 完成时，定是对过去的推测

。

4、

句中如有表示不肯定的话语，如：I am not sure; I don’t know 之类，常选may /might的各种形式

巩固提高

1. I’m going to Europe on vacation together with John if I ___ find the money.

A. can

B. might

C. would

D. need 2. --- ____you interrupt now? Can’t you see I’m on the phone?

--- Sorry Sir, but it’s urgent.

A. Can B. Should C. Must D. Would 2

3. I

use a clock to wake me up because at six o'clock each morning the train comes by A. must B. mustn't C. should D. shouldn't my house. A. couldn't

B. mustn't C. shouldn't

D. needn't 4. One of our rules is that every student ____ wear school uniform while at school. A. might

B. could

C. shall

D. will 5. Jack is a great talker. It’s high time that he _____ something instead of just talking.

A. will do

B. has done

C. do

D. did 6. Days later, my brother called to say he was all right, but ____ say where he was. A. mustn’t

B. shouldn’t

C. wouldn’t

D. mightn’t

7. --- I don’t really like James. Why did you invite him?

--- Don’t worry. He

come. He said he wasn’t certain what his plans were.

A. must not B. need not C. would not D. might not 8. It _______ be the postman at the door, It’s only six o’clock.

A. mustn’t B. can’t C. won’t D. needn’t

9. If you ______ smoke, please go outside. A. can B. should C. must D. may 10. --- Will you read me a story, Mummy? --- OK. You ________ have one if you go to bed as soon as possible. A. might B. must C. could D. shall 11. --- Shall I inform him of the change of the schedule right now? --- I am afraid you _____,in case he comes late for the meeting . A. will B. must C. may D. can 12. They have arrived at lunchtime but their flight was delayed. A. will B. can C. must D. should 13. You_________ buy a gift, but you can if you want to. A. must B. mustn’t C. have to

D. don’t have to

14. --- 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.

A. could B. shall C. must D. may 15. --- May I take this book out of the reading room?

--- No, you . You read it in here. A. mightn’t B. won’t C. needn’t

D. mustn’t

16. --- I take the book out? --- I'm afraid not. A. Will B. May C. Must D. Need 17. "You __ have a wrong number," she said. "There's no one of that name here. " A. need B. can C. must D. would 18. --- Sorry, Professor Smith. I didn't finish the assignment yesterday.

--- Oh, you have done it as yesterday was the deadline.

19. --- Why____ you be talking so loudly while others are studying?

--- I'm terribly sorry. A. shall B. must C. will D. may 20. --- We want someone to take charge of this project.

--- _____ the young man have a try? A. may B. shall C. will D. need 21. I promise she ____ get a nice present on her twentieth birthday. A. shall B. should C. must D. would 22. The World Wide Web is sometimes jokingly called the World Wide Wait because it ____be very slow. A. should B. must C. will D. can 23. --- Is there any flight to New York today?

--- I think there _____, for the weather is too bad. A. may not be B. shouldn't be C. can't be D. mustn't be 24. Mr. Bush is on time for everything. How ____it be that he was late for the opening ceremony? A. must B. should C. can D. may 25. --- Is it good to look up every new word when I come across it in reading?

--- No. You ___because you are likely to guess the meaning from the context. A. can't B. mustn't C. don't have to D. ought not to Cultural Corner Activity 1: Read this passage and answer the following questions:

1. What does Mr McCorquodale like doing when he travels?

2. What does he take with him when he travels?

3. On what conditions is he allowed to stick a pin in the map?

4. How does he evaluate China?

5. Why does Mr McCorquodale like traveling?

3