小学情态动词用法课件

2024-05-11

小学情态动词用法课件（精选6篇）

篇1：小学情态动词用法课件

2) must是说话人的主观看法，而have to则强调客观需要。Must只有一般现在时， have to 有更多的时态形式。

1. he play isn’t interesting, I really must go now.

2. I had to work when I was your age.

3) 表示推测、可能性(只用于肯定的陈述句)

1. You’re Tom’s good friend, so you must know what he likes best.

2. Your mother must be waiting for you now.

四、dare, need

1) dare作情态动词用时, 常用于疑问句、否定句和条件从句中, 过去式形式为dared。

1. How dare you say I’m unfair?

2. He daren’t speak English before such a crowd, dare he?

3. If we dared not go there that day， we couldn’t get the beautiful flowers.

2) need 作情态动词用时, 常用于疑问句、否定句。在肯定句中一般用must, have to, ought to, should代替。

1.You needn’t come so early.

2. ---- Need I finish the work today?

---- Yes, you must. / No, you needn’t.

3) dare和 need作实义动词用时，有人称、时态和数的变化。在肯定句中，dare后面常接带to的不定式。在疑问句和否定句中，dare后面可接带to或不带to的不定式。而need后面只能接带to的不定式。

1. I dare to swim across this river.

2. He doesn’t dare (to) answer.

3. He needs to finish his homework today.

五、shall, should

1) shall 用于第一人称，征求对方的意见。

What shall we do this evening?

2) shall 用于第二、三人称，表示说话人给对方的命令、警告、允诺或威胁。

1. You shall fail if you don’t work hard.(警告)

2. He shall have the book when I finish it.(允诺)

3. He shall be punished.(威胁)

六、will, would

1) 表示请求、建议等，would更委婉。

Will / Would you pass me the ball, please?

2) 表示意志、愿望和决心。

1. I will never do that again.

2. They asked him if he would go abroad.

3) would表示过去反复发生的动作或某种倾向。would表示过去习惯时比used to正式，且没有“现已无此习惯”的含义。

1. During the vacation, he would visit me every other day.

2. The wound would not heal.

4) 表示估计和猜想。

It would be about ten o’clock when she left home.

七、should, ought to

1) should, ought to表示“应该”，ought to表示义务或责任，比should语气重。

1. I should help her because she is in trouble.

2. You ought to take care of the baby.

2) 表示劝告、建议和命令。should, ought to可通用，但在疑问句中常用should。

1. You should / ought to go to class right away.

2. Should I open the window?

3) 表示推测

should , ought to (客观推测), must(主观推测)。

1.He must be home by now. (断定他已到家)

2.He ought to/should be home by now.(不太肯定)

3. This is where the oil must be.(直爽)

4. This is where the oil ought to/should be.(含蓄)

八、情态动词+不定式完成式(have done)

1) can / could + have done在肯定句中表示“本来可以做而实际上能做某事”，是虚拟语气;在疑问句或否定句中表示对过去行为的怀疑或不肯定, 表示推测。

1. You could have done better, but you didn’t try your best. (虚拟语气)

2. He can’t have been to that town.(推测)

3. Can he have got the book?(推测)

2) may / might +不定式完成式(have done)

表示对过去行为的推测。不能用于疑问句中，没有虚拟语气的用法。Might所表示的可能性比may小。

1. He may not have finished the work .

2. If we had taken the other road, we might have arrived earlier.

3)must +不定式完成式(have done)

用于肯定句中，表示对过去行为的推测。意为“一定、想必”。其疑问、否定形式用can，can’t代替。参看1) can / could + have done表示推测。

1. You must have seen the film Titanic.

2. He must have been to Shanghai.

4)should +不定式完成式(have done)

用于肯定句中，表示对过去行为的推测。

He should have finished the work by now。

表示“本应该做而实际上没有做某事”，其否定式表示某种行为本不该发生却发生了。可以与ought to +不定式完成式(have done)互换。

1. You ought to / should have helped him. (but you didn’t.)

2. She shouldn’t have taken away my measuring tape, for I wanted to use it.

5) needn’t +不定式完成式(have done)

表示“本来不必做而实际上做了某事”。

You needn’t have watered the flowers, for it is going to rain.

6) will +不定式完成式(have done)

主要用于第二、三人称，表示对已完成的动作或事态的推测。

He will have arrived by now.

篇2：小学情态动词用法课件

(1).表示能力、许可、可能性。表示能力时一般译为“能、会”，即有种能力，尤其是生来具备的能力，此时may 和must均不可代替它。如：She can swim fast, but I can’t . 她能游得很快，但我不能。I can see with my eyes. 我用眼睛看。

(2).表示许可，常在口语中。如：You can use my dictionary. 你可以用我的字典。

(3).表示推测，意为“可能”，常用于否定句和疑问句中，此时can’t 译为“ 不可能”。如：Can the news be true? 这个消息会是真的吗?—Can it be our teacher?那个人有可能是我们老师吗?—No, it can’t be our teacher. He is on a visit to the Great Wall.不可能。咱们老师正在游览长城呢。

【例题】—I think Miss Gao must be in the library. She said she would go there. —No. She __be there, I have just been there. A.can’t B.mustn’t C.needn’t D.wouldn’t

【解析】根据下文“我刚去过那儿”可知，应为“ 不可能”， can’t 表示推测[答案] A

2. could的用法：

(1).can的过去式，意为“ 能、会”，表示过去的能力。如：He could write poems when he was 10. 他十岁时就会写诗。

(2). could在疑问句中，表示委婉的语气，此时 could 没有过去式的意思。如:Could you do me a favour? 你能帮我个忙吗?—Could I use your pen? 我能用一下你的钢笔吗? —Yes, you can.可以。(注意回答)

3. may的用法：

(1).表示请求、许可，比can 正式，如：May I borrow your bike? 我可以借你的自行车吗?You may go home now. 现在你可以回家了。

【例题】—_______ I borrow your MP3? —Sure . Here you are. A. May B.Should C.Must D. Would

【解析】在此处表示请求，意为“ 做……可以吗”。答案：A

(2) .表示推测，谈论可能性，意为“ 可能，或许”，一般用于肯定句中。如：It may rain tomorrow . 明天可能会下雨。She may be at home. 她可能在家呢.

(3) .may的过去式为might ，表示推测时。可能性低于may。如：He is away from school. He might be sick.

他离开学校了，可能是他生病了。

(4) . 表示希望、祈求、祝愿，常可译为“祝愿”。通常是用may +主+V 例如：May you have a good time. 祝你过得愉快。May you be happy! 祝你幸福! May you succeed!祝你成功!

4. must的用法：

(1).must 表示主观看法，意为“必须、一定”。如：You must stay here until I come back.在我回来之前你必须呆在这儿。Must I hand in my homework right now? 我必须现在交作业吗?

(2) 其否定形式mustn’t表示“ 一定不要 ” “千万别” “禁止, 不许”. 如：You mustn’t play with fire. 你不许玩火。You mustn’t be late. 你一定不要迟到。

(3)对must引导的疑问句，肯定回答为must，否定回答为needn’t 或 don’t have to .如：—Must I finish my homework?我现在必须完成作业吗?—No, you needn’t.不，你不必。

(4)must表示有把握的推测，用于肯定句。如: The light is on, so he must be at home now.灯亮着，他现在肯定在家。

注意其反意问句的构成形式：

当must表示肯定的判断、推测时，其反意疑问句要用实际问句的助动词来构成。如：She must have seen the film before，hasn’t she?(注意反意疑问句的后半部分)You must have met uncle Wang in the shop yesterday，didn’t you? (注意反意疑问句的后半部分)

5. need的用法：

(1).need 表示需要、必须，主要用于否定句和疑问句中，其否定形式为needn’t，意为“没有必要，不必”。用need 提问时，肯定回答为 must，否定回答为 needn’t或don’t have to。如：—Need I stay here any longer? 我还有必要留在这儿吗?—Yes, you must .是的。—No. you needn’t /don’t have to. 不，你不必。

(2).need 还可以作实义动词，此时有人称、数和时态的变化，如果是人作主语后边多接动词不定式。如：I need to do it right now. 我需要马上做这件事。He needs to learn more about the girl.他需要多了解那个女孩。

如果是物作主语，一般用need doing 与 need to be done这种情况下应注意两点：

①.主动形式的动名词doing具有被动的含义;②.该动名词可以改为其动词不定式的被动形式而句子的意义不变。例如：. The door needs painting. = The door needs to be painted. 那扇门需要油漆一下。Your car needs mending. = Your car needs to be repaired. 你的车需要维修了。

6. dare 的用法：dare意为“敢、敢于”, 用法近似于need，有两种词性：

(1)dare 作为情态动词，多用于否定句、疑问句或条件句中，无第三人称单数形式，只有一般现在时和一般过去时。如：Dare he tell them what he knows? 他敢告诉他们所知道的情况吗?I daren’t ask her – will you do it for me? 我可不敢问她，你能帮我问问吗?

(2)dare 作为实义动词，此时有人称、数及时态的变化。如：He doesn’t dare to break his promise.他不敢食言。

注意：在口语中，dare 的各种形式常与不带to 的不定式连用。如：Do you dare tell her what I said?

篇3：情态动词热点用法导航

一、may/might, must, can的推测性用法

1.意义与适用范围

may表示“或许, 可能”, 用于肯定句, 但存在may not, 表示“可能不”;might表示“或许, 可能”, 可能性比may小, 用于肯定句, 表示对现在情况的推测 (也可用于过去时表示对过去情况的推测) , 但存在might not, 表示“可能不”, 比may not的可能性小;must表示“一定, 必定”, 用于肯定句;can表示“或许, 可能”, 用于疑问句和否定句。

例1:—Who is in the office?Can it be Li Ping?———谁在办公室里?有可能是李平吗?

—No, it can't be him.He has gone to Beijing.———不, 不可能是他。他到北京去了。

例2:—Will the plan work?———这计划会起作用吗?

—I think it may/might work.———我认为可能会起作用。

例3:You have just finished a long walk, so you must be very tired.你刚刚完成了长距离步行, 所以一定很疲劳吧。

例4:—Will he come this afternoon?———今天下午他会来吗?

—I'm not sure, he may not come.———我没有把握, 他可能不来。

例5:—Is this red pen Li Ping's?———这支红钢笔是李平的吗?

—No, it can't be his.His is a black one.———不, 不可能是他的。他的钢笔是黑色的。

【典例1】—_______the news that our headmaster has returned from abroad be true?

—No, it_______.

A.Can;can't

B.Can;mustn't

C.May;can't

D.Must;mustn't

【解析】A。第一空表示“可能”且用于疑问句, 因此应填Can;第二空表示“不可能”, 因此应填can't。

【典例2】—Will the final English exam that we will take at the end of this week be difficult?

—It_______be very difficult, but I'm not so sure.

A.must

B.can't

C.mustn't

D.may not

【解析】D。由but I'm not so sure可以推出该空可表示“可能不”, 因此可填may not。

【典例3】Since you have so much work to do, you_______be very busy.

A.can

B.may

C.must

D.need

【解析】C。Since you have so much work to do暗示该空表示“一定”, 因此应填must。

2.反意疑问句的构成

may, might, must, can等推测性情态动词所在句构成反意疑问句时谓语动词不能再用情态动词, 而应与其后的实义动词保持一致, 其时态的使用遵循下列原则:may/must/can't+原形动词, 表示对现在相关情况的推测, 反意疑问句应用一般现在时;may/must/can't+have done sth+过去时间状语, 表示对过去相关情况的推测, 反意疑问句用一般过去时;may/must/can't+have done sth的反意疑问句用现在完成时。

例1:It is so late, so he can't be at home, is he?现在太晚了, 所以他不可能在家, 是吗?

例2:Your father must have gone abroad for a meeting last Sunday, didn't he?你父亲上周日一定出国开会了, 是吗?

例3:The light in his room is out, so he may have gone to bed, hasn't he?他房间的灯熄了, 所以他可能已经上床睡觉了, 是吗?

【典例1】Now, your daughter must be at home doing her homework, _______she?

A.mustn't

B.needn't

C.isn't

D.can't

【解析】C。题干中的must表示推测, 且其后接原形动词, 因此反意疑问句用一般现在时。

【典例2】Your youngest brother may have gone to see a film last night, _______he?

A.hasn't

B.didn't

C.mayn't

D.doesn't

【解析】B。题干中的may表示推测, 且其后接have done+过去时间状语, 因此反意疑问句用一般过去时。

【典例3】This common actress can't have won the big prize, _______she?

A.can

B.has

C.did

D.may

【解析】B。题干中的can't表示推测, 且其后接have done的动词形式, 因此反意疑问句应用现在完成时。

二、may, must, can的非推测性用法

1.意义与用法

can还可表示“能, 会;有时也会;可以”, 常用来征求对方意见或向对方提出请求。may还可表示“可以”, 用来表示许可对方做某事、征求对方意见或向对方提出请求。must还可表示“必须, 应该”, 意义否定式为needn't, 表示“不必”;形式否定式为mustn't, 表示“不准, 禁止”。

例1:Can you speak to foreigners in English?你能用英语和外国人讲话吗?

例2:Can I use your English-Chinese dictionary to look up a word in?我可以用你的英语字典来查一个单词吗?

例3:May I have a word with you in your office now?现在我可以在你的办公室和你交谈一下吗?

例4:—Must I finish all of my task this week?———本周我必须完成所有的任务吗?

—No, you needn't.———不, 你没有必要。

例5:This river is very deep, so you mustn'swim in it.这条河很深, 所以你不可以在里面游泳。

【典例1】I'm not good at physics, so I'm afraid that I_______work out this difficul physics problem.

A.can't

B.mustn't

C.needn't

D.won't

【解析】A。I'm not good at physics暗示该空表示“不能”, 因此应填can't。

【典例2】Peter, don't you know that even gentle girl_______sbe very naughty?

A.must

B.may

C.can

D.shall

【解析】C。该空表示“有时会”, 因此应填can。

【典例3】Mary, it's already midnight._______you play the violin at such a late time?

A.Can

B.Must

C.May

D.Need

【解析】B。由句中隐含的责怪埋怨口吻可以推出该空表示“非得”, 因此应填Must。

【典例4】—Must I stop what I'm doing at present to help you to finish your work?

—No, you_______.

A.mustn't

B.needn't

C.can't

D.shouldn't

【解析】B。该空表示“不必”, 因此应填needn't。

【典例5】This is a garage, so you _______smoke in it at any time.

A.needn't

B.mustn't

C.won't

D.daren't

【解析】B。由This is a garage可以推出空档表示“不可以”, 因此应填mustn't。

2.委婉表达

might可以代替may, could可以代替can, 语气更为委婉、客气、礼貌, 但对其开头的一般疑问句做回答时应还原成may和can。

例1:—Could I watch TV for a while?———我可以看一会儿电视吗?

—Of course, you can.———当然可以。

例2:—Might I look at your photo taken on the Great Wall?———我可以看一下你在长城拍的照片吗?

—Yes, you may.———是的, 你可以。

【典例1】—Could I put you to the trouble of answering me a question?

—Yes, you_______.

A.could

B.might

C.can

D.must

【解析】C。could用于一般疑问句表示客气的请求时, 回答应还原成can。

【典例2】—Might I have a few minutes of rest now?I'm so tired.

—Yes, you_______.

A.might

B.may

C.could

D.need

【解析】B。might用于一般疑问句表示客气请求时, 回答应还原成may。

三、shall, should的用法

1.shall可表示“需要”, 用来征求对方意见, 用于一、三人称;shall还可以表示“命令, 警告, 威胁强制, 允诺”, 用于第二、三人称。

例1:There is not much time left, so you shall finish your homework immediately.时间不多了, 所以你必须立即完成家庭作业。

例2:You shall get my help if you accept my advice.如果你采纳我的建议, 我会帮助你的。

例3:Shall Li Ping clean the classroom in the shortest time?需要李平在最短时间之内打扫教室吗?

例4:—Shall I hand in my homework now?———我现在必须交上家庭作业吗?

—Yes, you must./No, you needn't.———是的, 你必须。/不, 你不必。

【典例1】—Shall I write down all the words on the blackboard now?

—No, you_______.

A.mustn't

B.can't

C.won't

D.needn't

【解析】D。由Shall I和No可以推出该空表示“没有必要”, 因此应填needn't。

【典例2】Time is very limited, so you_______get to that mountain village within fifteen minutes.

A.will

B.shall

C.can

D.may

【解析】B。Time is very limited暗示该空表示“必须”, 因此应填shall。

【典例3】You_______get my help when you come here, so don't be worried about it.

A.shall

B.must

C.need

D.should

【解析】A。该空意为“可以”, 表示承诺, 因此应填shall。

例4:Mary has got home._______she come here to see you immediately?

A.Will

B.Shall

C.May

D.Can

【解析】B。该空意为“需要”, 用于第三人称征求意见, 因此应填Shall。

2.should可表示“应该, 竟然”, 强调惊讶的情绪;表示“如果, 万一”, 位于句首构成条件状语从句 (省略if) 。

例1:As students, we should try to learn all the subjects well.作为学生我们应该尽量学好各门学科。

例2:Nobody can imagine the stone should be so heavy.没有人可以想象到这块石头竟然这么重。

【典例1】To tell you the truth, I have never expected such a beautiful girl_______ be so cruel to others.

A.can

B.may

C.should

D.would

【解析】C。由such a beautiful girl和s cruel to others之间的逻辑关系可以推出该空表示“竟然”, 因此应填should。

【典例2】_______a fire break out, you must sound the fire alarm in the shortest time.

A.Would

B.Could

C.Might

D.Should

【解析】D。空档表示“如果, 万一”, 因此应填should。

四、情态动词+have done sth的用法

1.may/might have done sth, 相对于现在/过去某一时刻可能已做某事;must have done sth, 相对于现在/过去某一时刻肯定已做某事;can't have done sth, 相对于现在不可能已经做了某事。

例1:—Where is my magazine?I can't see it now.———我的杂志哪儿去了?我看不见它了。

—Tom may have taken it———可能是汤姆拿了。

例2:The light in his room is on, so he might have come back.他房间的灯亮着, 所以他可能已经回来了。

例3:The little girl was crying.She might have lost her way.这小女孩在哭, 她可能已经迷路了。

例4:He isn't in his office.He must have gone to the playground.他不在办公室, 一定到操场去了。

例5:—I phoned you last night, but you didn't answer me.———昨晚我给你打电话但你没有接。

—Oh, I must have gone to sleep.———噢, 我一定睡着了。

例6:I saw him just now.He can't have gone to Beijing.我刚刚才看见他, 他不可能到北京去了。

【典例1】—I have looked for him everywhere but I can't find him.

—He _______home.

A.can have gone

B.must go

C.may go

D.must have gone

【解析】D。由I have looked for him everywhere but I can't find him.可以推出该空表示“一定已经回家了”, 因此应填must have gone。

【典例2】The door in her office is still open, so she_______very far.

A.can't go

B.can't have gone

C.shouldn't have gone

D.oughtn't to have gone

【解析】B。The door in her office is stil open暗示该空表示“不可能已经走了”, 因此应填can't have gone。

【典例3】Mary is sad now.She _______the bad news of her husband's death.

A.may know

B.can know

C.must know

D.may have known

【解析】D。is sad暗示该空表示“可能已经知道”, 因此应填may have known。

2.should/ought to have done sth, 本来应做某事但实际未做;shouldn't/oughtn't to have don sth, 本来不应该做某事但实际已做。

例1:You are late again.You should/ough to have come an hour earlier.你又迟到了, 你应该一小时之前就到了。

例2:You are ill again.You shouldn't/oughtn't to have worked so hard.你又病了, 本来你不应该这么辛苦工作的。

【典例1】You are still doing your homework .You_______it an hour and a half ago.

A.should finish

B.ought to finish

C.must have finished

D.should have finished

【解析】D。are still doing与an hour and half ago暗示该空表示“本来应该完成但实际没有”, 因此应填should have finished。

【典例2】Your father looks so sad.You _______with him.

A.shouldn't quarrel

B.oughtn't to quarrel

C.shouldn't have quarreled

D.can't have quarreled

【解析】C。由Your father looks so sad.可以推出该空表示“本来不应该争吵”, 因此应填shouldn't have quarreled。

3.needn't have done sth, 本来不必做某事但实际已做。

例1:You have to wait for the bus for at least an hour.You needn't have come so early.你得等至少一个小时的汽车, 你本来没有必要来得这么早。

例2:It is very warm today, so you needn't have worn so many clothes.今天非常暖和, 所以你本来没有必要穿这么多衣服。

【典例】The final exam turned out to be so easy, so you_______aboutit.

A.can't have worried

B.shouldn't have worried

C.oughtn't to have worried

D.needn't have worried

【解析】D。turned out to be so easy暗示该空表示“本来没有必要担心”, 因此应填needn't have worried。

五、need的用法

need作为情态动词只能用于否定句和疑问句, 用于疑问句时否定回答用needn't, 肯定回答改为must。

例1:—NeedIcleantheclassroom today?———今天我需要打扫教室吗?

—Yes, you must.———是的, 你必须。

例2:—Need she come here very early tomorrow morning?———明天早晨她必须很早就来这儿吗?

—No, she needn't.———不, 她不必。

【典例】—Need I do all the English exercises before school is over, Mr Smith?

—Yes, you_______.

A.need

B.must

C.shall

D.can

【解析】B。对need引导的一般疑问句做肯定回答时应将need改成must。

六、will, would的用法

will可用于第二人称来征求对方意见, 也可表示现在的意愿, 还可表示现在习惯性动作;would也可用于第二人称来征求对方意见, 常用于would you please, would you like to等结构, 语气委婉, 不是过去式;would还可表示过去的意愿和过去的习惯性动作。

例1:Will you help me to clean the doors and windows?你愿意帮助我擦门窗吗?

例2:If possible, she would sit like that for hours.如果有可能, 她总是那么坐着, 一坐就是几个小时。

例3:I'm free now.Would you like to go shopping with me?现在我有空了, 你愿意和我去购物吗?

【典例1】Tom, _______you hand me the dictionary?It is out of my reach.

A.shall

B.will

C.should

D.need

【解析】B。该空用于第二人称征求对方意见, 因此应填will。

【典例2】If it was possible, I _______go fishing with my brother after school was over.

A.should

B.could

C.would

D.ought to

【解析】C。由If it was possible可以推出空档表示“总是”, 强调过去习惯性动作, 因此应填would。

巩固与提高:

1.—Will our English teacher give us another chance to do this thing?

—He_______, but I'm not so sure.

A.must

B.can

C.may

D.need

2.Look, the flowers are all dead, so you_______ them enough water in time.

A.should give

B.must give

C.must have given

D.should have given

3.—Is the man standing over there our headmaster?

—No, he_______be our headmaster.Our headmaster has gone abroad.

A.mustn't

B.can't

C.won't

D.shan't

4._______you lose my English-Chinese dictionary, you have to buy a new one for me.

A.Should

B.Can

C.May

D.Shall

5.Look, your daughter is crying over there.In my opinion, you_______her so sad.

A.shouldn't make

B.shouldn't have made

C.mustn't have made

D.can't have made

6.Can't you see the young trees are all dead?You_______them enough water in the past few days.

A.can't give

B.can't have given

C.shouldn't have given

D.mustn't have given

7._______you be caught in a heavy rain, you can buy an umbrella in the nearest shop.

A.Can

B.May

C.Would

D.Should

8.—Sir, why do you want to fine me 100yuan?

—Don't you know nobody_______smoke at a gas station?

A.shall

B.must

C.need

D.will

9.—It is said that our English teacher has gone abroad for a visit.

—No, he_______.I saw him just now.

A.mustn't

B.needn't

C.shouldn't

D.can't

10.—Shall I come to help you with your housework after I finish my work?

—No, you_______.

A.shan't

B.won't

C.can't

D.needn't

11.—Mum, can I play computer games for some time after I finish today's homework?

—You_______get the permission to do so if you finish your homework on your own.

A.will

B.shall

C.must

D.need

12._______you meet with this kind of fierce animal, you must keep calm and try to get away.

A.Should

B.Would

C.Could

D.Might

13.You_______about the exam at all, because you have passed it with a very high mark.

A.needn't worry

B.needn't have worried

C.shouldn't have worried

D.can't have worried

14.Whether you read newspapers or magazines in our reading room, you_______keep silent.

A.may

B.need

C.shall

D.will

15.—I have just finished writing a 5000-word article.

—Then you_______be very tired.Sit down on the safa and have a rest.

A.must

B.need

C.shall

D.will

16.To my surprise, our daughter _______wear so many clothes on such a hot day.

A.could

B.would

C.should

D.might

17.Since it is your best friend's birthday party, I think that you_______show up in time.

A.may

B.can

C.need

D.should

18.All the teachers in our school are kind to and strict with us, so we _______look up to every one of them.

A.should

B.can

C.may

D.need

19.Since the terrible storm has come, you_______ set sail for that city in a short time.

A.needn't

B.can't

C.won't

D.shan't

20.To tell you the truth, at that time I wa very shocked that your child_______have said such unkind words to his teacher.

A.should

B.might

C.could

D.would

21.—Mary, is this your skirt?

—No, this skirt_______ be mine.My skirt is red.

A.may not

B.mustn't

C.can't

D.shan't

22.As you can see, the street is covered with snow, so you _______take care when you walk on it.

A.need

B.shall

C.can

D.will

23.As we all know, a gas station is a place where everyone_______smoke.

A.needn't

B.shan't

C.won't

D.mustn't

24.—_______I water all the flowers in our garden after I finish washing these clothes?

—No, you needn't.I have already watered them.

A.Can

B.Will

C.Shall

D.May

25._______the beautiful skirt put on that big desk be Mary's if it is not yours?

A.Can

B.May

C.Must

D.Should

26.—Perhaps you don't know I have been working in the field for almost half a day.

—Then, you_______be very tired.

A.need

B.will

C.shall

D.must

27.These rules are of great importance, so you_______pay much attention to them.

A.may

B.can

C.shall

D.will

28.Since you have won the big prize in the competition, you_______be very happy now.

A.can

B.need

C.must

D.would

29.Your secretary has already returned from abroad._______he come to see you now?

A.Will

B.Can

C.Shall

D.Would

30.This project, I think, is very complicated, so you_______take great care while carrying it out.

A.can

B.may

C.will

D.shall

31.—_______I help you to carry all the books to your classroom?

—No, you needn't.I can do it myself.

A.Shall

B.Can

C.Will

D.May

32.Your brother must have gone to visit that place of interest yesterday morning, _______he?

A.mustn't

B.hasn't

C.didn't

D.wasn't

33.—Will they pay a visit to the Great Wall of China at the end of this month?

—They_______visit it, but I'm not so sure.

A.can't

B.may not

C.must

D.need

34.I think that our English teacher _______home, for she isn't in her office now.

A.may go

B.may have gone

C.should have gone

D.ought to have gone

35.His youngest daughter is a very honest girl, so she_______your newly bought reference book.

A.can't steal

B.shouldn't have stolen

C.can't have stolen

D.oughtn't to have stolen

36.Our monitor is so excited now.He_______the news that he has won the big prize in the English writing competition.

A.must have known

B.must know

C.should have known

D.ought to have known

37.—That green skirt is really very beautiful.I_______it.

—It is really a pity that you didn't.

A.should buy

B.should have bought

C.must have bought

D.may have bought

38.My deskmate failed to pass the English exam.I_______him with his English.

A.need have helped

B.must have helped

C.may have helped

D.ought to have helped

39.Your daughter has a stomachache now.She_______so much iced food.

A.shouldn't have eaten

B.shouldn't eat

C.can't have eaten

D.needn't have eaten

40.You_______that expensive jacket.It cost you so much money.

A.oughtn't to buy

B.needn't have bought

C.can't have bought

D.oughtn't to have bought

答案与解析:

1.C。由but I'm not so sure.可以推出空档表示“可能”, 因此应填may。

2.D。题干含责怪埋怨的口吻, 因此应填should have given。

3.B。由Our headmaster has gone abroad.可以推出空档表示“不可能”, 因此应填can't。

4.A。空档表示“万一, 如果”, 因此应填Should。

5.B。空档表示“本来不应该让她”, 因此应填shouldn't have made。

6.B。由Can't you see the young trees are all dead?可以推出空档表示“不可能已经给予”, 因此应填can't have given。

7.D。空档表示“万一, 如果”, 因此应填Should。

8.A。空档表示“ (法律条文规定) 可以”, 因此应填shall。

9.D。由I saw him just now.可以推出空档表示“不可能”, 因此应填can't。

10.D。题干中的Shall表示“需要”, 因此空档表示“不必”, 应填needn't。

11.B。分析语境逻辑可知, 答话者在向对方做出承诺, 因此空档应填shall。

12.A。空档表示“如果, 万一”, 因此应填Should。

13.B。由because you have passed it with a very high mark.可以推出空档表示“本来没有必要担心”, 因此应填needn't have worried。

14.C。空档表示“必须”, 因此应填shall。

15.A。由I have just finished writing a5000-word article.可以推出空档表示“一定”, 因此应填must。

16.C。由wear so many clothes on such a hot day可以推出空档表示“竟然”, 因此应填should。

17.D。由Since it is your best friend's birthday party可以推出空档表示“应该”, 因此应填should。

18.A。由are kind to and strict with us可以推出空档表示“应该”, 因此应填should。

19.B。由空档前后语境逻辑可以推出空档表示“不能”, 因此应填can't。

20.A。由was very shocked可以推出空档表示“竟然”, 因此应填should。

21.C。由No和My skirt is red.可以推出空档表示“不可能”, 因此应填can't。

22.B。由the street is covered with snow可以推出空档表示“必须”, 因此应填shall。

23.D。由a gas station可以推出空档表示“不可以”, 因此应填mustn't。

24.C。空档用于第一人称来征求对方意见, 因此应填Shall。

25.A。空档表示“可能”且用于一般疑问句, 因此应填Can。

26.D。由I have been working in the field for almost half a day可以推出空档表示“一定”, 因此应填must。

27.C。由These rules are of great importance可以推出空档表示“必须”, 因此应填shall。

28.C。由have won the big prize in the competition可以推出空档表示“一定”, 因此应填must。

29.C。空档表示征求对方意见, 且用于第三人称, 因此应填Shall。

30.D。由is very complicated可以推出空档表示“必须”, 因此应填shall。

31.A。空档用于第一人称征求对方意见, 因此应填Shall。

32.C。陈述句含must have done+过去时间状语时反意疑问句动词应和must have后面的实义动词保持一致, 并用一般过去时的时态。

33.B。由but I'm not so sure.可以推出空档既不表示“不可能”也不表示“一定”, 而表示“可能”或“可能不”, 因此应填may/might或may not/might not。

34.B。由she isn't in her office now可以推出该空表示“可能已经回家”, 因此应用may have done的动词形式。

35.C。由His youngest daughter is a very honest girl可以推出该空表示“不可能已经偷了”, 因此应填can't have stolen。

36.A。由Our monitor is so excited now.可以推出该空表示“一定已经知道”, 因此应填must have known。

37.B。由语境逻辑可以推出该空表示“本来应该买了”, 因此应填should have bought。

38.D。该空表示“本来应该帮了”, 因此应填ought to have helped。

39.A。分析语境逻辑可以推出该空表示“本来不应该吃”, 因此应填shouldn't have eaten。

40.D。由It cost you so much money可以推出该空表示“本来不应该买了”, 因此应填oughtn't to have bought。

篇4：情态动词的用法

can是最常用的情态动词之一，表示说话人的语气或情感，没有人称和数的变化，在句子中不能单独作谓语，只能和紧挨着它的动词原形一起构成复合谓语。基本意思是“能；会”。can的否定式为can not，缩写为can’t。过去式为could。具体用法是：

1. 表示能力（如体力和脑力方面），意为“能；会”等。如：

①Can you speak English? 你会讲英语吗？

②Can you play the piano? 你会弹钢琴吗？

2. 表示请求或允许，多用在口语中，意为“可以；能”等。用于疑问句中用来提出要求，如：Can I…？“我可以……吗？”用来征求对方是否允许自己做某事，Can you…？“请你……好吗？”表示说话人的请求，如在句末加上please一词就显得更有礼貌了；用于否定句中表示不允许。如：

①Can I help you? 我能帮助你吗？

②Can you help me, please? 请你帮助我好吗？

③You can’t play basketball. 你不能玩篮球。

3. 表示可能。如：

①He can be at home now. 他现在可能在家。

②The moon can’t always be full. 月亮不可能常圆。

4. 表示怀疑。只能用于一般疑问句中，带有感情色彩。如：

Can it be true? 那会是真的吗？

5. 变否定句时，直接在后面加上“not”,可缩写成can’t或cannot, 但不能写成cann’t。如：

①He can swim.→He can’t swim.

②Emma can see the pen on the desk.→Emma cannot see the pen on the desk.

6. 变一般疑问句时，将can直接移到主语前（原主语的首字母改成小写，第一人称应变为第二人称）即可。如：

I can see an orange on the table.→Can you see an orange on the table?

其回答可用Yes. OK或Certainly等作肯定回答；用No或Sorry等作否定回答。如：

——Can you look after my books, please? 你能照看一下我的书吗？

——OK. 可以。

用Certainly回答。此时语气更为肯定。如：

——Can I see your guitar? 我能看看你的吉他吗？

——Certainly. 当然可以。

情态动词have to

have to意为“必须，不得不”，表示外界的客观要求，含有迫不得已的意味。这是一个比较特殊的情态动词，与其它的情态动词can, may, must等用法基本相同。不同之处是有人称和数的变化，否定式和疑问式的构成方式。

have to与别的情态动词一样也是后接动词原形，这是情态动词的共同特点。一般的情态动词所用的时态受到一定的限制，而且没有人称和数的变化。 have to可用于多种时态，而且不同的时态有不同的形式：一般现在时中主语为第三人称单数时，要用has to；一般过去时中，要用had to；一般将来时中，要用will have to。如：

①I have to take Bill to hospital．我必须带比尔去医院。

②Jill has to stay in the bed when she is sick．

当吉尔有病的时候，她不得不躺在床上。

③I had to sit down and rest every five minutes．

我不得不每五分钟坐下来休息一下。

④I’ll have to take you to see a doctor if you don’t feel well．

如果你觉得不舒服的话，我将不得不带你去看病。

have to的否定式一般要借助于助动词来构成。have to， has to，had to和will have to的否定式分别为don’t have to， doesn’t have to， didn’t have to和won’t have to。它的疑问式也要用助动词的相应形式构成。如：

①——Do you have to give up eating ice cream？

你必须放弃吃冰淇淋吗？

——No， I don’t have to， but I must eat less of it．

不，我不必，但是我必须少吃一点。

②What does she have to eat and drink？她必须吃什么，喝什么？

③We won’t have to worry about them．我们不必为他们担心。

情态动词must

must是最常用的情态动词之一，虽有词义，但不完整，不能单独在句中作谓语，必须与动词一起构成谓语，没有人称和数的变化，而且只有一种形式，表示强烈的感情。其主要用法归纳如下：

1.表示主观看法。常译为“必须、应当”。如：

①The students must obey the school rules．学生必须遵守校规。

②We must finish our homework every day.

我们每天都必须完成作业。

2.否定形式mustn’t表示“不应该”、“不可”、“不许”的意思，给人一种不能讲任何条件和借口的感觉。如：

①You mustn’t waste your time. 你不应该浪费时间。

②You mustn’t tell her about it. 你一定不要把这事告诉她。

3.否定回答用needn’t（不必），不用mustn’t。如：

——Must I hand in my exercise today? 我必须今天交练习吗？

——No, you needn’t. 不，不必。

4.表示说话人对事物的推断，只能用于肯定句，意为“一定；准是”，比may的语气肯定得多，否定句中多用can’t。如：

①Mr Smith must be a teacher．史密斯先生肯定是教师。

②Mr Li Yang must be over forty years old.

李阳老师一定是四十多岁了。

情态动词have to和must在用法上的区别

have to强调客观需要做的事情，即表示由于外界条件的要求而不得不去做某事；而must则强调说话者主观上应该去做某事。如：

①Mother is ill． I have to look after her at home．

妈妈病了，我不得不在家照看她。

②All of us must work hard at English．

我们大家都必须努力学习英语。

have to的否定形式不能在have后加not，而应借助于助动词do来构成。同样，其疑问形式也不可将have移到主语前，而应借助于助动词do来帮助。而must则可变化自身构成疑问和否定。且以must开头的一般疑问句，其肯定回答应用Yes，…must．其否定回答应用No，…needn’t．而不可用No，…mustn’t．。如：

①They don’t have to clean the classroom now．

他们不必现在打扫教室。

②——Must we finish our homework now？

我们必须现在完成家庭作业吗？

——Yes， you must．（No， you needn’t．）