1、初中英语情态动词知识点及经典练习题情态动词知识点总结：（一）情态动词的定义情态动词表示说话人对动作的态度，比如：需要，可能，意愿，猜测或者怀疑等等。（二）情态动词的特点1）有一定词义；2）不受主语人称和数的变化影响；3）与主要动词的原形（或称不带 to 的不定式）一起构成谓语（除 ought to 作固定词组看待） 。4）否定句中，在情态动词后面加 not。（三）情态动词有：must, shall, should, had better 词形无变化can(could), may(might), will(would) 词形有变化need 既可以是情态动词，也可以是实义动词，具有双重性。（四）情
2、态动词的基本用法1. can (could)1）表示会做某事，有能力做某事。意思 = be able to 其否定式 cant 表示“不能”。在过去时中用 could 和 couldnt. （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） 。He can speak English, but he cant speak Japanese.= He is able to speak English, but he isnt able to speak Japanese.I could smile but I couldnt speak when I was 2 mon
3、ths old.= I was able to smile but I wanst able to speak when I was 2 months old.区别：1、 can 只用于现在时和过去时(could), be able to 可用于各种时态。They will be able to tell you the news soon. 2、be able to 不与 can 连用，但可以和其他情态动词或助动词连用。He may be able to speak English very well some day in the future.3、用在过去时中，could 经常表示能够做
4、某事，事实上不一定去做，而 waswere able to 则表示“过去做成了某事” 。在否定句中两者可通用。2）用于征求意见Can /Could /May /Might I(we) do sth?Yes, you can/may. / Of course you can.No(Sorry), you cant. /mustnt.注意：此处的 could 和 might 都不表示过去，只是语气上的委婉，不用作回答。否定回答中，表示对他人造成一定伤害或影响，或表示违反了某种规定或法律时，用 mustnt 较好。e.g. Could I take the book out of the libra
5、ry? Sorry, you mustnt.May I smoke here? Im afraid you mustnt.表示过去能力时，could 提问，只能用 could 回答。e.g. Could you ride a bike when you were 4 years old? No, I couldnt. 3）表提出意见或请求Can/Could you (please) do sth? = Would you (please) do sth? （此句型中 some 不变 any）e.g. Could you please give me a hand?Would you pleas
6、e pass me some salt?4）表示允许或承诺 =maye.g. OK. You can /may come and find me at any time tomorrow.5）表示有一定把握的推测，用于否定句和疑问句。此时 cant 译为“不可能” 肯定句用 must。表示没有把握的推测，用 may /might。e.g. The window is broken. Who did it? It may be Mary. It cant be Mary. The window is in the mens toilet. Can it be anyone else? Then,
7、 it must be Bob. I saw him go into the toilet just now.He cant (couldnt) have enough money for a new car. 他不可能有足够的钱买新车。【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.cant B.mustnt C.neednt D.wouldnt【解析】根据下文“我刚去过那儿”可知，应为“不可能” ，ca
8、nt 表示推测答案 A2. may (might)may 表示“可以，可能” ，否定形式 may not，表示“不可以” 。1） 表示没有把握的推测， “可能，也许” 。可以指过去时间，也可以指现在时间，但语气更加不肯定。e.g. He may have a lot of work to do. = Maybe he has a lot of work to do.You may be right. = Maybe you are right.2）表示请求 “我可以吗？” 表示请求、许可，比 can 正式 e.g. You may /can go now.May I use your pen?
9、 Yes, you may. / Yes, please. / Go ahead.No, you cant. / mustnt. 在回答以 may 引起的问句时，多避免用这个词，而用其它方式，如 Yes, please. / Certainly. / Please dont ./ Youd better not. / No, you mustnt.等，以免显得太严峻或不客气。3） 、 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 suc
10、ceed！祝你成功！3. mustmust 表示“必须，肯定，一定” ， 否定形式 mustnt = must not 表示“禁止” 。1）表示必须，意思同 have toe.g. Must I do it now?Yes, you must.No, you dont have to. / No, you neednt. (注意：否定回答不用mustnt)Children mustnt play on the road because its too dangerous. (mustnt只表“禁止”)He doesnt have to go away from here. =He neednt
11、 leave here.区别：must 表达主观意愿的“必须” ，have to 表达客观上或按道理说“不得不” 。e.g. I must study hard.Its too late. I have to go now.must 没有人称和时态的变化，而 have to 有。e.g. He had to walk back home because he lost all his money.Mom will be away for a week, so we will have to do the cooking by ourselves.2）表示有把握的肯定句中的推测， “肯定，一定”
12、 ，只用于肯定句。He must be ill. He looks so pale. 他准是病了。他的脸色苍白。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，hasntshe?(注意反意疑问句的后半部分)You must have met uncle Wang in the shop yesterday，didnt you? (注意反意疑问句的后半部分)4.needneed 表示“需要” ，否定形式 neednt = need not “不必、不需要”1)、作情态
13、动词，仅用于否定句和疑问句。e.g. He neednt go home early yesterday. = He didnt need/have to go home early yesterday.Need I call him right now? Yes, you must.(注意：肯定回答不用 need)No, you neednt. /No, you dont have to.2） 、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：need sth./sb.need to do sth. 否定形式 dont need to = dont have to
14、表示“不必”e.g. I need some help. He needed to go home early yesterday.Do I need to call him right now? Yes, you do. / No, you dont.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：.主动形式的动名词 doing 具有被动的含义；.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
15、一下。Your car needs mending. = Your car needs to be repaired.你的车需要维修了。3） 、 need 作名词 be in (great) need of sth = need sth (badly) “非常需要某物”meet the need “满足需要（需求） ”there is/was no need (for sb) to do sth “某人没必要做某事”5. 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
16、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 darent 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 doesnt 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?你敢告诉她我说的话吗？I didnt dare look at him.我不敢看他归纳：need
17、和 dare 的用法1、need 和 dare 既可用作情态动词，也可用作实义动词。用作情态动词时，通常不用于肯定句而主要用于否定句和疑问句。用作实义动词时，可用于各种句式。2、其他用法：I dare say为固定习语，不是“我敢说”而是“我想” 。I dare day hell come again. 我想他会再来的。Neednt have done:表示本没必要做而做了6. shall 的用法：1）表征询意见，用于第一、第三人称疑问句。Shall I get some tea? 我给你点茶好吗？Shall the boy wait outside? 让那男孩在外面等吗？2）表说话人的意愿，
18、有“命令、允诺、警告、决心”等意思，用于第二、第三人称陈述句。You shall do as I say. 按我说的做。 （命令）You shall have my answer tomorrow. 你明天可以得到我的答复。 （允诺）He shall be sorry for it one day, I tell you. 有一天他会后悔的，我告诉你。 （警告）Nothing shall stop us from carrying out the plan. 什么也不能阻止我们执行这项计划。 （决心）归纳：在英语中，我们可以用其他多种方式提出我们的建议或征求对方意见。(1).用“Lets do
19、.”来提出建议。如：Lets go for a walk after supper.(2).用“What/How about.?”来提出建议；about 后接名词或动词 ing 形式。如：What about/How about a drink? What about/How about taking Tom with us?(3).用“Why not.?”来提出建议，表示“何不”not 面后接动词原形。 “Why not.?”实际上是“Why dont you/we.?”的简略形式。如：Why not meet at the school gate at eight? Why dont we
20、 stay here another day?(4).用“Would you like.?”来提出建议，意思是“你想要吗?”Would you like 后可接名词或不定式。如：Would you like a cup of tea? Would you like to go and see her?因此，如果我们说：“去游泳好吗?”英语中可有这样几种表达法：Shall we go for a swim? Lets go for a swim，shall we? What about/How about going swimming? Why not go for a swim? Would
21、you like to go for a swim? What do you think of going for a swim?6、 will 的用法1） 、表意愿，用于各种人称陈述句。 “愿意”I will do anything for you. 我愿为你做任何事。2） 、表请求，用于疑问句。Will you close the window? Its a bit cold. 请你把窗户关上好吗？有点冷。Wont you drink some more coffee? 再来一点咖啡好吗？注意：1、will 在 there be 句型中的形式及其句式变换。由于“一般将来时”的结构可以用“w
22、ill+动词原形”来表示，所以 there be 句型的一般将来时的形式就是 there will be。 （一定不能说 there will have）例如：There are many students in our school.There will be many students in our school. There will be a sports meeting next week.一定不能说：There will have a sports meeting next week.2、will 与 be going to do something 区别：. be going t
23、o 表示近期、眼下就要发生的事情，will 表示的将来时间则较远一些，如：He is going to write a letter tonight. He will write a book one day. be going to 表示根据主观判断将来肯定发生的事情，will 表示客观上将来势必发生的事情。He is seriously ill. He is going to die. He will be twenty years old. be going to 含有“ 计划，准备”的意思，而 will 则没有这个意思，如：She is going to lend us her boo
24、k.He will be here in half an hour.在有条件从句的主句中，一般不用 be going to,而多用 will,如：If any beasts comes at you, Ill stay with you and help you.7. should 的用法1） 、表义务。意为“应该” （某件事宜于做） ，用于各种人称。否定形式 shouldnt = should not 表示“不应该”You should be polite to your teachers. 你对老师应该有礼貌。2） 、表推测，意为“想必一定、照说应该、估计”等。The film shoul
25、d be very good as it is starring first-class actors. 这部新电影是一流演员主演的，估计拍得很好。They should be home by now. 照说他们现在应当已经到家了。8.would 的用法1）表意愿I said I would do anything for you. 我说过我愿意为你做任何事。2）表委婉地提出请求、建议或看法。常见句型：表请求 Would you please do? OK. / Sorry, .Would you like sth? Yes, please. / No, thanks.Would you li
26、ke to do sth? Id love to.Id love to, but.(注意：以上句型中，some 不变 any)9. ought to 1）表义务，意为“应该” （因责任、义务等该做） ，口气比 should 稍重。You oughtnt to smoke so much. 你不应该抽这么多烟。2）表推测，暗含很大的可能，语气较弱。Theres a fine sunset; it ought to be a fine day tomorrow. 今天有晚霞，明天应该是个好天。10、used to 表示过去的习惯动作或状态，现在不复发生或存在。疑问式和否定式有两种。I usednt
27、 (didnt use) to smoke. 我过去不抽烟。Used you (Did you use) to go to school on foot? 你过去常步行去学校吗？11、had better do 表示“最好是做” ，否定形式 had better not doe.g. Youd better not drink so much coffee.区别：Its better for you to do more exercise and not to have so much junk foo归纳：一、不同情态动词的否定意义也不同：1.（1）.cant 可译为“不会” ，如：I ca
28、nt play basketball.我不会打篮球。（2）当句子表推测时，用 cant 表达不可能，如：He cant be ill. He is playing chess with Tom.他不可能病了，他正和 Tom 下棋呢。（3）cant 还可用来回答“ May I ? ”这样的问句。如：May I come in ? 我可以进来吗？No, you mustnt. / cant.不，你不能。（4）cant 还可用于固定习语中。cant help doing 禁不住，情不自禁cant wait to do something 迫不及待地要做如：She cant help crying.她
29、不禁大哭起来。The children cant wait to open the box.孩子们迫不及待地想打开盒子。2. may 的否定式为 may not，译成“可能不” ，如：He may not be at home.他也许不在家。3.（1）mustnt 表示不许，不可。如：He mustnt leave his room.他不许离开他的房间。You mustnt talk in class.你们不可以在课上说话。(2) mustnt 也可用于以 may 表示要求时的否定回答中。如： May I stand here? 我可以站在这里吗？ No, you mustnt (cant).
30、不，不行。4.（1）neednt 意为“不必” 。如：You neednt meet him unless youd like to.你不需要见他，除非你愿意。（2）neednt + have+动词的过去分词，表没必要做而做了的动作，暗含时间或精力上的浪费。如： You neednt have bought it.你没必要买它（但你却买了） 。5. shouldnt 表示不应该。 如：You shouldnt feel so unhappy over such little things.对于这种小事，你不应该感到这么不高兴。二、含有情态动词的疑问句的回答:1.对 may 引出的问句，可以有下
31、列回答方式：Yes,you may. Yes, of course. Yes, certainly. Sure . No, you mustnt. No, you cant.2.对 must 引出的疑问句，回答方式为：Yes, must. No, neednt/ dont have to.3.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）4. shall 引出的疑问句用于第一人称，表
32、示征求对方意见或客气的请求。其回答方式有以下几种：Yes, please. All right. No, thank you.5.would you的回答方式有以下几种：Yes, I will. (No, I wont.) Sure . (Im sorry , I cant.) All right/ OK/ With pleasure. Certainly. (No, thank you .) Yes, please.【例题】 Would you do me a favour and pass on my thanks to Lily?_.A.Thats right B.With pleasu
33、re C.It doesnt matter D.No trouble【解析】A.意为“对了” ，B.意为“乐意效劳”, C.意为“没关系” D.意为“不费事” 。答案：B三、:情态动词表示推测的用法:1、 “情态动词+动词原形”表示对现在的推测。1） 、can 表示推测时一般用于否定句或疑问句。如：That man cant be her husbandshe is still single.Who is knocking at the door? Can it be the postman?2） 、must 表示肯定的推测，一般用于肯定句中。如：He must be in his offic
34、e now.Mr Li must be working now，for the lights in his office are still on.3） 、might 表示推测时不一定是 may 的过去时，只是表示其可能性较小。如：The man may be the headmaster.Where is Mr Li?He might be working in his office. May Mr Li come?He might not come here.4） 、Could 表示推测时，语气 can 比要弱，说话者留有余地。如： Could it be an animal?It cou
35、ld not be，because it is not moving.5） 、Should 表示推测的可能性比较大，仅比 must 的可能性小一点。如：It is already 10 oclock now they should be there.2、情态动词表示对过去可能发生的动作或存在过的动作的推测性用法。1） 、 “must +have done/been-”表示“过去一定发生过某事或存在过某种状态” ，不用于“musnt+have-”形式。如：She must have seen the film before，hasntshe?(注意反意疑问句的后半部分)You must have
36、 met uncle Wang in the shop yesterday，didnt you? (注意反意疑问句的后半部分)2） 、 “should +have done /been-”表示“本应当做某事，而实际上并没有做” ；“shouldnt+完成式”表示“本来不应当做，而实际上却做了” 。以上结构常带有说话者的责备的感情色彩。如：You should have finished your homework earlier (but in fact you did not finish it on time).You shouldnt have gone to bed when you
37、woke up at five (but in fact you went to bed again then).3） 、 “neednt+完成式”表示“本来没有必要做某事，而实际上却做了” 。如：There was plenty of time. She neednt have hurried .4） 、 “cant /couldnt+have done /been-”表示“过去不可能发生了某事或存在过某种状态” 。如：I saw him just now. He cant have gone to Japan.She said the man couldnt have stolen her
38、 car.5） 、 “could+have done/been-”表示“过去本来能够，可以做某事或成为某种状态，而实际上没有” ，说话者有些遗憾。“could sb. have done /been-？”是它的问句形式。如：You could have stayed with the Smiths while you were in New York (but in fact you stayed in a nearby hotel .) Could Mr Li have helped this girl student?6） 、 “may/might+完成式”表示“过去可能，本来可以于某事而
39、实际上没有干” ，might 的可能性较小，语气较弱。如：He may have finished reading the book. She might have given you some help，however bus she was.拓展：情态动词后跟进行式，表示“想必正在” ， “可能正在” ， “应当正在”等意。Its twelve oclock. They must having lunch. 现在是十二点。他们一定正在吃饭。They may be discussing problem. 他们可能正在论讨这个问题。He cant be telling the truth. 他
40、说的不可能是真话。She shouldnt be working like that. Shes still so weak. 她不应当那样干，她身体仍那么虚。情态动词易混点归纳易混点一: can 和 be able to:两者表示能力时用法相同，但 can 只有原形“can”和过去式“could”两种形式，在其他时态中要用 be able to 来表示。另外 be able to 常常指经过努力，花费了时间和劳力之后才能做到某事。易混点二:can 和 may1. can 和 may 均可用来征求意见或许可，意为 “可以” ，一般可互换使用。如：Can/ May I help you ? 我能
41、帮助你吗？ 2. can 和 may 表示可能性时的区别：1)在肯定句中用 might，may，must，不用 can2)在疑问句中表示推测用 can，不用 might，may，must3)在否定句中用 cant（不可能） ，不用 may，must。如：She may be in the classroom .她可能在教室里。Where can they be now?他们现在可能在哪儿？That cant be true.那不可能是真的。易混点三: may be 和 maybe用法区别 常用位置may be may 为情态动词，be 为动词原形 句中，作谓语maybe 副词，大概、也许，相当
42、于 perhaps 句首，作状语例如：He may be wrong , but Im not sure.也许他错了，但我也不确定。易混点四：cant 和 mustnt1. cant 根据其基本用法可译为：（1）不会。如：I cant speak English .我不会说英语。（2）不能。如：We cant do it now because its too dark.天太黑了，我们现在干不了。（3）否定句中表示推测。 “不可能” ，如：The man cant be our teacher because he is much younger than our teacher.那个人不可能
43、是咱们老师，他年轻得多。2. mustnt 意为“禁止、不许” ，用来表达命令，表示强烈的语气。如：You mustnt play football in the street. Its too dangerous.你不可以在街上踢足球，太危险了。易混点五：must 和 have to1.must 侧重于个人意志和主观上的必要。have to 侧重于客观上的必要，可用于现在时、过去时和将来时。2. have to 可以用于多种时态；而 must 只用于一般现在或将来。如：The composition is due to hand in this morning, so I had to fi
44、nish it last night.作文今天早晨到期，因此我不得不昨天晚上完成。易混点六: used to do / be used to doing / be used to do/ be used for doing sthused to do 表示过去常常发生的动作，强调过去，只用于过去，注意用 to do，不用 doing形式；be used to doing 意为“习惯做” ，be 可有各种时态；be used to do 意为“被使用去做,”为被动语态形式。be used for doing sth“用作”如：My father used to eating meat.我父亲过去
45、起床晚，但现在不得不早起了。She is used to eating meat.她习惯吃肉。He wasnt used to eating in a restaurant.他不习惯在饭店吃饭。A knife can be used for cutting things.(刀可以用来割东西)/ A knife can be used to cut things.(刀可以用来割东西)经典练习题：1. I _ you, because I I must be wrong.A. dare not ask B. dare not C. dare not asking D. dare to not as
46、k2. There _ some flowers in the garden.A. were used to be B. used to be C. uses to be D. used to be having3. “_ I take it out?“ “Im sorry, you _.“A. Could .couldnt B. Might.might not C. Could.can D. May.cant4. You were stupid to climb tree. You _ hurt yourself.A. may didnt you ?A. should post B. sho
47、uld have posted C. must have posted D. ought to post.6. All the lights are on, miths _ up.A. must get B. is getting C. must be getting D. would get7. He _ lead a but he _ not make it drink.A. will.can B. may.can C. may.dares D. dare.can8. “Need we do this job now?“ “Yes, _.“A. you need B. you should C. you must D. you can9. _ to have lunch with us today?A. Do you likes B. Would you like C. Will you liked D. Have you liked10. He said that you _ watch TV all the evening if you wished.A. may B. must C. can D. might11. -Is John coming by train? -He should, but he _ not. He
