“情深意厚”之情态动词

刘颖桂

在英文中，情态动词是使用频率极高的一类词。不同的情态动词呈现说话者不同的态度，表达说话者不同的情感，听话人自然也会因此有不同的心理感受。例如，你的朋友们对你说“Well do all we can to help you.”，这里的will 便体现了朋友们帮助你的意愿，关心你的情感，而你也会因为这份关爱而快乐。再如，你的室友对你说：“Must you make so much noise, Tom?”，这里的must 则向你传递了室友的不满情绪，你也会意识到是自己行为不妥，影响了他们。可见，情态动词虽不起眼，却能传递丰富的情感。在英语学习中，如何领会小小情态动词所蕴含的深情厚意呢？毫无疑问，首先得了解它们的用法。这也正是本文所要解析的问题。下面就结合近几年的高考题，分析归纳一下常用的情态动词的重要用法，以便同学们能正确运用它们，领会它们传递的情感和态度。

一、 can 和could

1． 表示“能力”，指现在或将来的，用can ；指过去的，用could。 例如：

(1) Many of us can use the computer now, but we couldnt ten years ago.

(2) If it were not for the fact that she_____sing, I would invite her to the party.（2006福建）

A. couldnt B. shouldnt

C. cant D. might not

2． 在口语中，can和 could可以代替may, 表示“许可”，could的语气比can 更委婉，但答语中不可用could，应还原成can。例如：

—Can / Could I use your bicycle?

—Of course, you can.He said I could use his computer.

3. can和could都可用来表示对现在或过去情况的推测，用于疑问句或否定句，对现在情况的推测，后接一般式或进行式；对过去情况的推测，后接完成式或完成进行式。即：

“can (could ) / cant (couldnt) do / be doing / have done / have been doing”。例如：

(1) Who can it be at this time of day?

(2) He is very busy. He cant / couldnt be watching TV at home.

(3) —Is Jack on duty today?

—It_____be him. Its his turn tomorrow. （2006 湖南）

A. mustnt B. wont

C. cant D. neednt

(4) —Well, he_____have gone far.

—his coats still here. （2005 重庆）

A. shouldnt B. mustnt

C. cant D. wouldnt

注意（一）： can在肯定句，可表示“有时候也……”，指一种客观的可能性。例如：

(1) Even experienced teachers can make mistakes.

(2) The climate of the south can be pretty cold in winter.

(3) The World Wide Web is sometimes jokingly called the World Wide Wait because it_____be very slow. （2005 浙江）

A. should B. must C. will D. can

注意（二）： could have done 还可表示一种虚拟“本来能够做，而未做”。例如：

He paid for a seat , when he_____have entered free. （2005 山东）

A. could B. would C. must D. need

3． 构成“Cant you / we do ...？”的句式，“难道……吗？”表示请求或提议。例如：

Cant you give him a hand?

Cant we walk there?

4． 构成“ can not / never ... too ...”或 “can not ... enough ”句型。表示“无论怎么……也不过分；越……越好”。例如：

(1) One can not be too careful.

(2) He is such a great man that we can not praise him too much.

(3) I can not thank you enough.

5. 构成“can not help doing / can not help but do / can not but do”结构。表示“禁不住；不由得；不得不”。例如：

I can not but admire his courage. （我不能不佩服他的勇气）

6.can & be able to

(1) can表示“能力”时,主语可以是人或物,而be able to 的主语常是有生命的东西.如： This book can give you all the information you need.

(2) can只有现在和过去两种时态形式，（can 和could）,而be able to 有各种时态形式。例如：

I hope the little I have been able to do is of some help to you.

(3) can 的过去式could 表示过去能够做……，而was / were able to ，表示过去做成了某事。例如：

The maths problem was very difficult , but everyone was able to work it out.

二、 may & might

1． 表示许可或征询对方许可，其否定形式可以用may not ；但表示“不可以；禁止： 阻止”等意思时，则用must not (mustnt)。例如：

(1) You may go now.

(2) May I come in ?

(3) He said that I might use the phone.

(4) Tom, you_____ leave all your clothes on the floor like this! （2005 全国卷）

A. wouldnt B. mustnt

C. neednt D. may not

2． 表示对现在或过去情况的可能的推测，用于肯定或否定句中，构成“may(not) / might (not) do / be doing / have done / have been doing”句型。指现在的情况后接一般式或进行式；指过去的情况时，后接完成或完成进行式。其中，might比may 语气更不肯定。例如：

(1) Helen_____go on the trip with us, but she isnt quite sure yet. （2005 安徽）

A. shall B. mustC. mayD. can

(2) We_____have proved greatadventurers , but we have done the greatest march ever made in the past ten years. （2006 天津）

A. neednt B. may not

C. shouldnt D. mustnt

注意： might have done 还可表示虚拟，“本来可以做……，但未做”。例如：

He might have called for help. (but he didnt.)

3． 构成“may / might as well do ”句型，表示“还是做……为好，不妨做……”。例如：

He seems to have known everything. You may as well tell him the truth.

4． 构成“may + 主语+ 动词原形”结构，表示“祝某人/物……”。例如：

May you succeed in the coming exam!

May our friendship last forever!

三、 Must & have to

1. must 表示“必须；应该”，是说话人的主观看法；have to 则表示客观情况。回答must的问句时，否定式为“neednt 或dont have to , 表示“不必”，不可用must not (mustnt) , 因为must not (mustnt) 表示“禁止，不可以”。例如：

(1) —Must I be there before 6 am?

—Yes, you must. / No, you neednt (dont have to).

(2) The TV set is broken. I have to buy a new one.

(3) You mustnt play football in the street.

注意：可用have got to 代替have to.

2. must 表示对现在或过去情况的肯定的推测，指现在的情况，后接一般式或进行式；指过去的情况，后接完成式或完成进行式，即：must do / be doing / have done / have been doing

I was on the highway when this car went past followed by a police car. They_____at least 150km an hour.（2005 重庆）

A. should have been doing

B. must have been doing

C. could have done

D. would have done

3. must 表示固执、不满，意为“偏偏，偏要”，常用于“if you must”结构。例如：

(1) —May I smoke here?

—If you_____ , choose a seat in the smoking section. （2006 山东）

A. should B. could C. may D. must

(2) John, look at the time,_____you play the piano at such a late hour? （2005 全国）

A. Must B. Can C. May D. Need

四、 will & would

1. 表示“意志；意愿”，可用于多种人称。此时，will指将来，would指过去。例如：

He wont go with us.

He said that he would help us.

I told him not to go , but he would not listen.

2. 表示向对方提出请求，多用于第二人称，此时，would 的语气比will更委婉，答语中，不可用would，而应还原为will。例如：

Will / Would you give him a message when you see him?

Yes, of course. / Yes, I will.

3. will表一般的倾向，习惯，“总是，老是”；would则表过去经常或反复的动作。例如：

Fish will die without water.

The door wont lock. （门老是锁不上）

Every time he came to China, he would visit the Great Wall.

注意： used to do 也表示过去的习惯或经常发生的动作，但它侧重于表达过去与现在的对比，有“过去经常怎样，而现在不那样了”的含义；would 仅表示过去某一段时间常发生的行为，所以句中须有时间状语限定。例如：

I used to get up early.

I would get up early on Sundays.

4. would 可构成“would like / love to do”句型，“想做什么”；若指过去想做什么，而实际未做，则不定式用完成式，即：would like / love to have done。例如：

I would like to have gone to the concert last night , but I had to work out the plan.

5. would 可构成“would rather (not) do”句型，表示“现在或将来宁愿做（不做）以及“would rather (not ) have done”，表示“过去宁愿做什么，而实际没做”。例如：

Id rather stay at home reading. (Id rather not go there.)

Id rather not have told him the news. （实际上已经告诉了）

注：这一句型中，只用would, 不用will.

五、 shall

1. 用于第一、三人称，表示向对方征求意见。例如：

(1) All the visitors are waiting outside, Dr Wang. Shall they come in together or separately?

(2) —Whats the name?

—Khulaifi,_____I spell that for you? （2006北京）

A. shall B. would C. can D. might

注意： may 用于请求对方的许可；shall 用于征求对方的意见。比较：

May I have a look? （我可以看一下吗？）

Shall I have a look? （要不要我看一下？）

1. 与第二、三人称连用，表示说话人的允诺、决心、威胁、警告、命令或法律、文件等的规定。例如：

(1) You shall get an mp4 as your birthday present this year. （允诺）

(2) Nothing shall stop me from going there. （决心）

(3) You shall be sorry for what you have done , I tell you. （威胁/警告）

(4) Nobody shall say a word when he comes in. （命令）

(5) The fine shall be paid in cash. （规定）

(6) “The interest_____be divided into five parts, according to the agreement made by both sides,” declared the judge. （2004 重庆）

A. may B. should C. must D. shall

六、 should

1. 表示义务、责任、建议，“应该”，（可换为ought to） 例如：

(1) You should make an apology to your parents.

(2) I often see lights in that empty house. Do you think I_____report it to the police?（2004 广西）

A. should B. may C. will D. can

2. 表预期，“应该会，想必会， 一定会……吧”，是比较有依据的推测，（等于ought to）

(1) There_____be any difficulty about passing the road test since you have practiced a lot in the driving school. （2005 上海）

A. mustnt B. shant

C. shouldnt D. neednt

(2) They set off at 7 am. They should have arrived there by now. (他们七点就动身了，现在应该已经到了吧)

3. 表惊讶、遗憾，“竟然；居然”。例如：

(1) You cant imagine that such a well-behaved gentleman should be so rude to a lady.

(2) Im glad that his story should have won the first prize.

4. should 表示委婉谦逊的语气，具有“可，倒”之意。例如：

I should advise you not to do that again. （我倒劝你别那样做了）

5. should / ought to have done 表示该做而实际上未做；shouldnt / ought not to have done 表示不该做却做了。例如：

—Ill tell Mary about her new job tomorrow.

—You_____her last week. （2004 福建）

A. ought to tell B. would have told

C. must tell D. should have told

6. 用于语气较强的假设中或虚拟条件中，表示“万一”。例如：

If she should know the truth (= Should she know the truth), she would be greatly depressed.

If she should fail to come, ask Tom to work in his place.

7. 用于表示命令、请求、建议类动词或名词后的名词性从句中，should 可省略。例如：

He refused our suggestion that he (should) leave the company.

8. 用于以lest , for fear that , in case 等引导的状语从句中，表示“以免；唯恐”。例如：

He made a list in case he should forget what to buy.

七、 need

1. 表示“必须，有必要”，用于疑问问句和否定句。回答need 开头的疑问问句时，肯定句应用must，不可用need 。例如：

—Need / Must I go there at once ?

—Yes, you must. / No, you neednt (dont have to)

2. need not (neednt ) have done 表示“不必做某事而实际上已做了”。例如：

As you worked late yesterday, you_____have come this morning.（2006 陕西）

A. neednt B. maynt

C. cant D. mustnt

八、 had better

had better ，“最好……；还是……好”，表示建议。语气比should 和ought to 更委婉，后接动词原形，否定式为had better not do，还可省略主语及had；疑问句中，将had 提前。例如：

(1) Youd better not tell him the bad news.

(2) —Had you better go at once?

—Yes, we had better. / No, wed better not.

(3) Better take your umbrella.

九、 dare

表示“敢做……”，多用于疑问句和否定句，过去式为dared.

She dare not go out alone at night.

—Dare you swim across the river?

—Yes, but years ago I dared not .

练一练：

1. Jenny_____have kept her word. I wonder why she changed her mind.

A. must B. should C. need D. would

2. —Could I borrow your dictionary ?

—Yes, of course you_____ .

A. might B. will C. can D. should

3. He_____you some help, even though he was very busy.

A. may give B. might give

C. may have given D. might have given

4. —Shall I tell John about it ?

—No, you_____ , Ive told him already.

A. neednt B. wouldnt

C. mustnt D. shouldnt

5. I wonder how he_____that to his parents.

A. dare to say B. dare saying

C. not dare say D. dared say

6. —I stayed at a hotel while in New York.

—Oh, did you? You_____with Jenny.

A. could have stayed B. could stay

C. would stay D. musthave stayed

7. I wish to visit the West Lake this summer, _____?

A. do I B. dont I

C. would I D. may I

8._____I tell the secret to Peter? No, you mustnt.

A. Must B. Need C. May D. Shall

9. You must have read the science fiction last week,_____ ?

A. mustntyou B. havent you

C. didnt you D. dont you

10. Where_____Mrs Smith be?

A. can B. must C. may D. need

11. —Mum, Ive been studying English since 8 oclock._____I go out and play with Tom for a while ?

—No, Im afraid not . Besides, its raining outside now.

A. Cant B. Wouldnt

C. May not D. Wont

12. —We want someone to design the new art museum for us.

—_____ the young fellow have a try?

A. May B. Shall C. Will D. Need

13. You_____him so closely; you should have kept your distance.

A. shouldnt follow

B. mustnt follow

C. couldnt have been following

D. shouldnt have been following

14. You know he is not going to let us leave early if we_____get the work done.

A. cant B. may not

C. shouldnt D. mustnt

15. Naturally, after I told her what to do, my daughter_____go and do the opposite!

A. may B. can C. must D. should

Keys: 1. B2. C3. D4. A5. D6. A7. D8. C9. C10. A11. A12. B13. D14. A15. C