單個(gè)情態(tài)動(dòng)詞分析.doc

單個(gè)情態(tài)動(dòng)詞講解1.can(could)1).表示能力，意為“能，會(huì)”，用can, could, be able to均可，could是can的過(guò)去式。區(qū)別是：can只有過(guò)去時(shí)could，而be able to有多種時(shí)態(tài)。John can speak three foreign languages fluently. John could swim when he was four.I regretted that I hadnt been able to drive him home.Will you be able to help me learn English tomorrow? 明天你能幫助我學(xué)習(xí)英語(yǔ)嗎？2）表示可能（理論上或是邏輯判斷上）。Thetemperaturecanfallto60。氣溫可降至60Anybody can make mistakes.表示推測(cè)或可能性，常用于否定句和疑問(wèn)句Can he be at school? Today is Sunday. He cant be at school.There is no light in the room. Can she have gone to bed?對(duì)過(guò)去的推測(cè)She could have gone out with some friends yesterday.It was silly to throw the TV out of the window. It could have hit somebody.You are late again. You could have got up earlier.3）表示請(qǐng)求或許可 （ Could 比 Can 更加客氣，can比may更正式）Can I park my car in front of your office?CanIhavealookatyournewpen? Heaskedwhetherhecouldtakethebookoutofthereadingroom.Could I use your bike now? -Certainly. Go ahead. Yes, you can4）表驚異、懷疑、不相信等態(tài)度。主要用于否定句、疑問(wèn)句或感嘆句中。Wherecan(could)theyhavegoneto?他們會(huì)去哪兒了呢？Hecant(couldnt)beoversixty.他不可能超過(guò)六十歲。Howcanyoubesocareless?你怎么這么粗心？5）比較委婉客氣地提出問(wèn)題或陳述看法。Can(Could)youlendmeahand?幫我一把好嗎？Imafraidwecouldntgiveyouananswertoday.恐怕我們今天不能給你答復(fù)。2. may and might 1) 表示可能性; 表不太可能的推測(cè), might可以指過(guò)去時(shí)間，也可以指現(xiàn)在時(shí)間，但語(yǔ)氣更加不肯定, may/might have done 對(duì)過(guò)去的揣測(cè)Helen may go on the trip with us, but she isnt quite sure yet.Theymightbehavingameeting,butImnotsure.He may be busy these days.Shemaynotknowaboutit.Hewasafraidtheymightnotagreewithhim.Your math teacher may / might be in his office.注意：用may表示推測(cè)一般不用于疑問(wèn)句，在疑問(wèn)句中通常用can來(lái)代替。 Can he be at home? 他可能在家嗎？ Can it be true? 這可能是真的嗎？ - It may be, or may not be. 2) 表示允許和請(qǐng)求 might不表示過(guò)去時(shí)，而是表示口氣比較婉轉(zhuǎn)。You may take whatever you like. 你喜歡什么就拿什么。He told me that I might smoke in the room. 他告訴我可以在房間里抽煙。May (Might) I ask for a photo of your baby? 我可以要一張你寶寶的照片嗎？May I come in ? May I watch TV now? Yes, you may. May/ Might I have a talk with you? 我可以和你談?wù)剢幔?May/Might I come into the room to see my mother? - No, you mustnt. She needs to have a good rest.提示：May I . ?問(wèn)句常見(jiàn)的肯定回答和否定回答。may引起的問(wèn)句時(shí)，多避免用這個(gè)詞，而用其它方式肯定回答Yes, please. / Certainly. / Yes, of course. / Sure. Go ahead, please.否定回答 No, you cant. (最常見(jiàn))/ No, you mustnt.(具有強(qiáng)烈禁止的意思)Please dont. / Youd better not. / I dont think you can. / Im sorry its not allowed.3) 表示祝愿 May you succeed. 祝你成功 May you be happy. 祝你快樂(lè)。 May that day come soon.希望這一天早日到來(lái)。4）may/might as well Now that you are here, you may as well try your best. 還是的好 All the shops are closed; we may as well go back. You might as well speak out your mind. 你還是把你的想法說(shuō)出來(lái)吧。 may well do sth. He may not well go with ushe hates travel.5）might用于虛擬 If he came here tomorrow, he might have a chance of talking with her.3. must and have to1）表示義務(wù),意為“必須”= have to (must 現(xiàn)在；將來(lái)的必須 而且是主觀看法 ,have to 有多種時(shí)態(tài) 而且強(qiáng)調(diào)客觀情況)I really must stop smoking now.I had to leave early because I wasnt feeling well.Must I come here? Yes, you must. No, you neednt / dont have to - Must I get to the station before three oclock?- Yes, you must. ( No, you neednt. )2） must 表示推測(cè) 意思非?？隙?“一定是”“一定會(huì)”,不用于疑問(wèn)句 must用于表示推測(cè)，它的肯定程度比may, might, could大得多，一般只用于肯定句。 (1) must do(這里的do通常是狀態(tài)動(dòng)詞或系動(dòng)詞)表示對(duì)現(xiàn)在狀態(tài)的推測(cè)。He must be very lazy, for his desk is very untidy. Carol must get very bored with her job. She does the same thing every day.He must be ill. He looks so pale.Shes wearing a diamond necklace. She must have a lot of money.He is absent today, and something must have happened to him.She must be at home now, as I just called her.(2) must be doing表示對(duì)現(xiàn)在動(dòng)作或狀態(tài)的推測(cè)。 Put on more clothes. You must be feeling cold with only a shirt on. 多穿點(diǎn)兒衣服，你只穿一件襯衣，肯定覺(jué)得冷。(3) must have done表示對(duì)過(guò)去的動(dòng)作或狀態(tài)的推測(cè)。He must have gone over the article, hasnt he?It must have rained last night, didnt it?The ground is wet. It must have rained last night. I didnt hear the phone. I must have been asleep. 提示must表示推測(cè)只用于肯定句，否定句和疑問(wèn)句要用can, could來(lái)代替must。Hes just had his lunch. He cant be hungry already. 他剛吃過(guò)午飯，不會(huì)餓的。They have just arrived here. They cant know many people. Leslie walked past me without speaking. He cant/couldnt have seen me.3）用于指 偏要、硬要 （ 令人不快的事） The car must break down just when we were in the jungle. (偏要)- Could I have a word with you, mum? - Oh, dear, if you must. Who is the girl standing over there? - Well, if you must know, her name is Mabel. Why must it rain today? 為什么偏偏在今天下雨？When I was taking a nap, a student must knock at the door. 正當(dāng)我午睡時(shí)，偏偏一個(gè)學(xué)生在這個(gè)時(shí)候來(lái)敲門。4)must可用來(lái)表示根據(jù)邏輯推理必然要發(fā)生的事，可譯為“必然會(huì)，總是會(huì)”。We all must die. 我們都會(huì)死。 Truth must be out. 真相必然會(huì)大白的。Winter must be followed by spring. 冬天到了，春天還會(huì)遠(yuǎn)嗎？4）禁止 (否定句)You mustnt make noises in the library. (禁止) (注：mustnt沒(méi)有表推測(cè)的意思)must和have to的區(qū)別:1）must表示有做某一動(dòng)作的必要或義務(wù)，強(qiáng)調(diào)主觀看法，可譯為“必須，應(yīng)該”。. Everyone must obey the rule. We must do everything step by step. Teachers must be patient enough with their students.2） must含有說(shuō)話者的強(qiáng)烈決意(表示主觀的看法)，have to 則表示外力環(huán)境或習(xí)慣使然(即表示客觀的必要，作“不得不”解)。I must study hard. 我必須努力學(xué)習(xí)。(發(fā)自內(nèi)心的決定) I have to study hard. 我不得不努力學(xué)習(xí)。(外界因素逼迫) You must stay for supper. 你必須留下來(lái)吃晚飯(because I want you to) You have to stay for supper. 你得留下來(lái)吃晚飯。(because there is nowhere else to go)3 ) must只有一種形式，而have to可有多種時(shí)態(tài)。They had to put off the sports meet due to the bad weather. These last two days he has had to take a rest at home.4) must的否定式和have to的否定式的意思完全不同。You must keep it a secret. You mustnt tell anyone. (mustnt表示“禁止”) You dont have to tell me the secret. 你不必告訴我這個(gè)秘密。(dont have to意思是“沒(méi)有必要”= dont need to)4.shall和should:1.shall (1) 疑問(wèn)句中，表示征詢意見(jiàn)或請(qǐng)求指示，用于一、三人稱疑問(wèn)句。Shall I carry it for you? Shall we sing a song?Shall they wait outside?Shall the waiter bring meals to your room?提示：Shall I open the window? 我打開(kāi)窗子好嗎？ Will you open the window? 你打開(kāi)窗子好嗎？(第二人稱用will) Shall he open the window? 他打開(kāi)窗子好嗎？(2) 陳述句中，表示說(shuō)話人的意愿，有“命令、強(qiáng)制，允諾、警告、威脅，決心”等意思，用于第二、三人稱陳述句中。 You shall do as I say. No, he shant go.不! 他不能去。（表命令） He shall be sorry for it one day, I tell you.我告訴你，總有一天他會(huì)后悔的。(警告)You shall fall behind in your exam if you keep playing. Nothing shall stop us from carrying out the plan.什么也阻止不了我們執(zhí)行這項(xiàng)計(jì)劃。(決心) He shall have the book when I finish reading. 我看完這本書(shū)就給他看。(允諾) I shall do my homework after reading this story book. 讀完這本故事書(shū)后我就做作業(yè)。You shall get the justice that you want.你會(huì)得到你想要的公平。（表允諾）You shall not use my camera if you dont use it properly.如果你不正確使用，我不會(huì)讓你使用我的照相機(jī)（表警告）Nothing shall stop us from carrying out this plan.什么也阻擋不了我們實(shí)施這項(xiàng)計(jì)劃。（表決心）2.should (1) 表示義務(wù)，意為“應(yīng)該”(某件事宜于做)，用于各種人稱。Children should obey their parents.兒童應(yīng)該服從他們的父母。 One shouldnt be selfish. 人千萬(wàn)別自私。 Customers who get bad service should complain, shouldnt they? 沒(méi)有得到滿意服務(wù)的顧客應(yīng)該抱怨，不是嗎？You should be polite to your teachers. 你對(duì)老師應(yīng)該有禮貌。 You shouldnt waste any time. 你不應(yīng)該浪費(fèi)時(shí)間。表示義務(wù)，意為“應(yīng)該”(因責(zé)任、義務(wù)而該做)，口氣比should稍重。 We ought to defend our country. 我們應(yīng)當(dāng)保衛(wèi)我們的國(guó)家。You ought to respect your parents. 你應(yīng)當(dāng)尊敬你的父母。Oughtnt we to do everything possible to stop pollution? 難道我們不應(yīng)當(dāng)盡可能地制止污染?2）表推測(cè)，意為“想必一定、照說(shuō)應(yīng)該、估計(jì)”等表示對(duì)過(guò)去、現(xiàn)在或?qū)?lái)情況的某種推測(cè) Thefilmshouldbeverygoodasitisstarringfirstclassactors 這部新電影是一流演員主演的，估計(jì)拍得很好。Theyshouldbehomebynow.照說(shuō)他們現(xiàn)在應(yīng)當(dāng)已經(jīng)到家了。It should be fine tomorrow. Its nearly seven oclock. Jack should be here at any moment. Should be doing 對(duì)現(xiàn)在的動(dòng)作的推測(cè) 表應(yīng)該做但卻沒(méi)做He should be taking a bath now.The boys shouldnt be playing football. They should be at school. Should have done 對(duì)過(guò)去的推測(cè) 表應(yīng)該做但卻沒(méi)做You shouldnt have entered the teachers office without permission. 表示推測(cè)，暗含很大的可能，可譯為“應(yīng)該是，會(huì)是”。Prices ought to come down soon. 價(jià)格可能會(huì)很快下跌。Han Mei ought to know his telephone number. Theres a fine sunset; it ought to be a fine day tomorrow. 今天有晚霞，明天應(yīng)該是個(gè)好天。ought to和should一樣，表示對(duì)現(xiàn)在或以前應(yīng)做的事卻沒(méi)做的責(zé)怪、批評(píng)。You ought to be washing your clothes. Why are you playing Ping-Pong?You ought to have handed in the exercise last week. 你上周就應(yīng)當(dāng)交練習(xí)。(可你沒(méi)交，含責(zé)備的意思。)He ought to have asked me before he took my bike. 他在用我自行車之前應(yīng)該和我講一聲。3) 常與what, how, why等詞連用，表示意外、驚訝等情緒。 How should I know? 我怎么會(huì)知道呢?Why should I fear? 我為什么會(huì)害怕？ What should she do but cry for help? 除了呼救外，她還能干什么？ I dont know why you should think I did it. 我真不知道你憑什么認(rèn)為這件事是我干的。should表示吃驚、贊嘆、不滿等情緒，也是近幾年來(lái)的高考熱點(diǎn)。Its wonderful that you should have achieved so much in these years.這幾年你們有了這么大的成就真了不起。You cant imagine a gentleman like him should treat a lady so rudely.你想象不出來(lái)象他這樣一位紳士竟然會(huì)如此粗魯?shù)貙?duì)待一位女士。 4）ought to 與should的比較。ought to 和should的含義較近，但不完全相同ought to表示“應(yīng)該”， 是從“義務(wù)”或“按理推斷”的角度來(lái)講的。should則是從說(shuō)話人的個(gè)人看法這一角度來(lái)講的。 You are her mother. You ought to look after her. 你是她的母親，你應(yīng)當(dāng)照管她。(是道義上的責(zé)任，不能和should互換。) We should encourage him, for we are his classmates. 我們應(yīng)該鼓勵(lì)他，我們是他的同班同學(xué)啊！提示：表示“義務(wù)”時(shí)，我們?cè)诳谡Z(yǔ)中可以用had better或be supposed to 來(lái)代替should和ought to。 If you are not well, you had better ask Alice to go instead. 如果你不舒服，你最好叫艾麗絲代替你去。Im supposed to be there at 8 oclock. 我應(yīng)該八點(diǎn)到那里。5.will和would:1）will和would可用于第二人稱疑問(wèn)句，表示請(qǐng)求和建議等。would比 will委婉客氣。Willyouclosethewindow?Itsabitcold. Wontyoudrinksomemorecoffee?再來(lái)一點(diǎn)咖啡好嗎？ Will you have some tea? 你喝點(diǎn)茶，好嗎？ Will you share your happiness with us? 你可以把你的歡樂(lè)與我們共享嗎？ Would you pass this book to the student in the last row? 必背：Will / Would you . ? 表示請(qǐng)求和建議的答復(fù)?？隙ɑ卮?Yes, please. 是的，請(qǐng)。 Certainly. 當(dāng)然可以。Sure. 當(dāng)然了。All right. 好??！否定回答Im sorry. I cant. 對(duì)不起，不行。No, thank you. 不，不行。No, I wont. 不，不行。比較： Would you like . ? 表示邀請(qǐng) / Do you like .? 表示習(xí)慣 Do you like going/ to go the cinema? 你喜歡看電影嗎？Yes, I go to the cinema a lot. 是的，我經(jīng)常去看電影。 Would you like to go to the cinema tonight? Yes, Id love to. 非常樂(lè)意。2）will和would可表示意志、愿望和決心，用于各種人稱陳述句。1）表意愿，用于各種人稱陳述句。 I will do anything for you. I said I would do anything for you. He wont do what hes toldIll do my best . (意愿) I will never do such a thing again. (決心) I will never tell you the secret. 我永遠(yuǎn)不會(huì)告訴你這個(gè)秘密。 They would not let him in because he was poorly dressed. Theywouldnthaveanythingagainstit.他們不會(huì)有什么反對(duì)意見(jiàn)。3）will和would可表示推論或猜測(cè)。The patient took the sleeping pills an hour ago. He will be asleep now. 病人一小時(shí)前吃的安眠藥，現(xiàn)在應(yīng)該睡著了。 It would be about ten when he left home. 他大約在十點(diǎn)鐘離開(kāi)的家。 I thought he would have told you about it. 我認(rèn)為他已告知你此事。 It would be raining when she went home. 她回家時(shí)可能正在下雨。It would be about ten when he left home. (表料想或猜想)3）will和would可表示某種傾向或習(xí)慣性動(dòng)作。will表示現(xiàn)在的習(xí)慣動(dòng)作，would表示過(guò)去的習(xí)慣動(dòng)作 Fish will die without water. (習(xí)慣性、傾向性)He would be nervous when he met strangers. 遇見(jiàn)陌生人時(shí)他總是很緊張。In class he would ask some silly questions, and his classmates would laugh at him. 課上，他總是問(wèn)一些蠢問(wèn)題，他的同學(xué)們總是嘲笑他。Last year our English teacher would sometimes tell us stories in English after class. (過(guò)去的習(xí)慣動(dòng)作,比used to正式，并沒(méi)有“現(xiàn)已無(wú)此習(xí)慣”的含義。但used to表現(xiàn)在不做了)4）非情態(tài)動(dòng)詞的用法用于非人稱主語(yǔ)時(shí)，表示物體的固有性質(zhì)和傾向 This glass will not crack under heavy pressure. Fishwilldieoutofwater.魚(yú)離開(kāi)水就不能活。 Thedoorwontopen.這門打不開(kāi)。Theboywillsittherehourafterhourlookingatthetrafficgoby. He promised he would never smoke again. (will的過(guò)去式)那男孩常常坐在那里好幾個(gè)鐘點(diǎn)，看著車輛行人通過(guò)。will表示將來(lái)時(shí)間時(shí)，不可用于條件狀語(yǔ)從句，但will表示意愿或決心時(shí)，可用于條件狀語(yǔ)從句。 If you will read the book, Ill lend it to you. If you will give up smoking, your health will improve. 6. need and dare 過(guò)去時(shí) dared need 和dare一樣，作為情態(tài)動(dòng)詞時(shí)，主要用于否定句和疑問(wèn)句，一般不用于肯定句中(在肯定句中常被 must, have to, ought to, should等情態(tài)動(dòng)詞取代)。need和dare一樣，也可以作行為動(dòng)詞，可用于肯定句、否定句和疑問(wèn)句中。行為動(dòng)詞need有人稱和數(shù)的變化。need1)need 情態(tài)動(dòng)詞 無(wú)時(shí)態(tài)；人稱的變化 多用于疑問(wèn)句和否定句作為情態(tài)動(dòng)詞，它的詞形只有need一種形式。無(wú)過(guò)去式和單三形式Y(jié)ou neednt return the book now. Need I hand in my homework now? 我現(xiàn)在就要交家庭作業(yè)嗎？- Need he finish the article next week.- Yes, he must.- No, he neednt. (= he doesnt have to)-Need I come? -Yes, you must. -我需要來(lái)嗎？ -需要。 You neednt telephone him now. 你現(xiàn)在不必打電話給他。 I dont think you need worry. 我想你不必發(fā)愁。neednt have done 本沒(méi)有必要做，但是做了You neednt have waited for her, as