情態(tài)動詞的定義

1、情態(tài)動詞的定義情態(tài)動詞的定義：情態(tài)動詞是一種本身有一定的詞義 ，表示說話人的情緒，態(tài) 度或語氣的動詞，但不能單獨作謂語，只能和其他動詞原形 構(gòu)成謂語。We can be there on time tomorrow.我們明天能按時去那兒。May I have your name?我能知道你的名字嗎?Shall we begin now?我們現(xiàn)在就開始嗎?You must obey the school rules.你必須遵守校規(guī)。情態(tài)動詞數(shù)量不多，但用途廣泛，主要有下列： can (could), may (might), must, need, ought to, dare (dared),

2、 shall (should), will (would).詞,則在助動詞之前，疑問句中情態(tài)動詞的位置: 情態(tài)動詞在句中放在謂語動詞之前，謂語動詞前若有助動 ,情態(tài)動詞則在主語之前。I can see you. Come here.我能看見你，過來吧。He must have been away.他一定走了。What can I do for you?你要什么?How dare you treat us like that ！ 你怎能那樣對待我們!情態(tài)動詞的特點：情態(tài)動詞無人稱和數(shù)的變化，情態(tài)動詞后面跟的動詞 需用原形，否定式構(gòu)成是在情態(tài)動詞后面加"not"。個別情態(tài)動詞有

3、現(xiàn)在式和過去式兩種形式，過去式用來表達(dá)更加 客氣，委婉的語氣，時態(tài)性不強(qiáng)，可用于過去，現(xiàn)在或?qū)?來。He could be here soon.他很快就來。We can't carry the heavy box.我們搬不動那箱子。rm sorry I can't help you.對不起，我?guī)筒簧夏?。情態(tài)動詞的用法：1 can (could)表示說話人能，可以，同意，準(zhǔn)許，以及客觀條件許可,could 為 can 的過去式。Can you p ass me the books?你能給我遞一下書嗎Could you help me, pl ease?請問,你能幫助我嗎？What

4、 can you do?你能干點什么呢？Can you be sure?你有把握嗎？can和could只能用于現(xiàn)在式和過去式兩種時態(tài)，將來時態(tài)用 be able to來表示。He could help us at all.他完全可以幫助我們。With the teacher's hel p,l shall be able to sp eak English correctly.由于老師的幫助，我將能準(zhǔn)確地講英語。2 may (might)可以，表示說話人同意，許可或請求對 方許可。You may take the book home.你可以把書帶回家去.May I come in?我可

5、以進(jìn)來嗎？May I use your dictionary?我可以用你的詞典嗎？You may put on more clothes.你可以多穿點衣服.He said he might lend us some money.他說他可以借給我們一些錢。may否定式為 may not,縮寫形式是mayn't.種表示過might是may 的過去式，有兩種用法，去式，一種表示虛擬語氣，使語氣更加委婉，客氣或?qū)?能性的懷疑。He told me he might be here on time.他說他能按時間來。Might I borrow some money now.我可以借點錢嗎？H

6、e might be alive.他可能還活著。must用來指一般現(xiàn)在時和一般將來時，過去式可用haveto的過去式代替。I must finish my work today.我今天必須完成我的工作。You mustn't work all the time.你不能老是工作。Must I return the book tomorrow?我必須明天還書嗎？After such a long walk, you must be tired.走了這么長的路，你一定困了。He must be the man I am looking for.他一定是我要找的人。He had to go b

7、ecause of somebody's callinghim that day.那天他要走是因為有人叫他。must + have + 過去分詞,表示現(xiàn)在對過去事物的推測。He must have told my p arents about it.他一定把這件事情告訴我父母親了。He must have received my letter now.他現(xiàn)在一定收到我的信了。It's six o'clock already, we must have been late again.已經(jīng)六點鐘了，我們一定又遲到了。must和have to的區(qū)別：must表示說話人的主觀

8、思想， have to表示客觀需要。You must do it now.你必需現(xiàn)在就干。（說話人認(rèn)為必須現(xiàn)在干）I have to go now.我得走了。（客觀條件必須現(xiàn)在走）4 need需要多用在否定式或疑問句中Need I attend the meeting tomorrow?我需要明天參加會議嗎？You need not hand in the paper this week.這一周你不必交論文。need是一個情態(tài)動詞，他的用法完全和其他情態(tài)動詞一 樣,但need還可當(dāng)作實義動詞使用，這時need就象其他動 詞一樣，有第三人稱，單復(fù)數(shù)，后面加帶to的動詞等特性。I need a b

9、ike to go to school.我上學(xué)需要一輛自行車。Do you need a dictionary?你需要詞典嗎？She needs a necklace.她需要一條項鏈。needn't + have + 過去分詞 表示過去做了沒必要做的事 情。You needn't have taken it seriously.這件事情你不必太認(rèn)真。5 dare敢 多用在否定或疑問句中。The little girl dare not sp eak in p ublic.小女孩不敢在公眾面前說話。Dare you catch the little cat?你敢抓小貓嗎？dare

10、除用作情態(tài)動詞外，更多的是當(dāng)實義動詞使用，用法 同實義動詞一樣，要考慮人稱，單復(fù)數(shù),時態(tài)等。Do you dare to walk in the dark?你敢黑夜走路嗎?He doesn't dare to tell the teacher what happ ened that day.他不敢告訴老師那天發(fā)生的事。6 ought應(yīng)當(dāng),應(yīng)該 后面跟帶有to的動詞不定式。You ought to read these books if you want to know how to rep air the motorcar.如果你想知道如何修理汽車，你應(yīng)該讀這些書。You ought

11、to bring the child here.你應(yīng)該把孩子帶來。句型。指過去動作，表示一件事情該ought + to have done 做而未做。You ought to have been here yesterday.你昨天就應(yīng)該來。ought not to have done 句型。表示一件不該做的事情卻做了。You ought not to have taken the book out of the reading-room.你不應(yīng)該把書帶出閱覽室。7 will (would)決心,愿望。 would為will的過去式,可用于各人稱。r II do my best to catc

12、h up with them.我要盡全力趕上他們。r II never do it again, that's the last time.我再不會做那件事情了 ，這是最后一次。He said he would help me.他說他會幫助我。will, would用于疑問句表示說話人向?qū)Ψ教岢稣埱蠡蛟儐?用would比will更婉轉(zhuǎn)，客氣。It's hot. Will you open the windows?天氣太熱了，你能打開窗戶嗎？Will you help me to work it out?你能幫我解這道題嗎？Would you like some coffee ？

13、給你來點咖啡怎樣?8 Shall, should 表示命令,警告,允諾,征求,勸告,建議驚奇。You should hand in the exercise book.你應(yīng)該交作業(yè)本兒了。This should be no p roblem.這應(yīng)該沒問題。Shall we go now.我們現(xiàn)在可以走了嗎？Why should I meet him ？為什么我要見他？9 have to,不得不,必須，表示客觀條件只能如此，而must則 表示主觀思想必須。I have to go now.我現(xiàn)在得走了。I have to cook for my child.我得給孩子做飯。You must be

14、 here on time next time.你下次一定要按時來。We must go to get the timetable ourselves.高考常見語法一虛擬語氣.語氣的定義和種類。1 語氣(mood)語氣是動詞的一種形式，表示說話人對某一行為或事情的看 法和態(tài)度。2語氣的種類a.陳述語氣：表示動作或狀態(tài)是現(xiàn)實的、確定的或符合事實的，用于陳述句、疑問句和某些感嘆句。如:每個問題都有兩個方There are two sides to every question.面。Were you busy all day yesterday?昨天一整天你都很忙嗎?How good a teach

15、er she is!她是多好的一位老師啊！b.祈使語氣：表示說話人對對方的請求或命令。如：Never be late again! 再也不要遲到了。Don 'forget to turn off the light. 別忘了關(guān)燈。c.虛擬語氣：表示動作或狀態(tài)不是客觀存在的事實，而是說 話人的主觀愿望、假設(shè)或推測等。如：If I were a bird, I could fly in the air.如果我是一只小鳥，我就能在空中飛行。I wish I could p ass the examination.我希望我能通過考試。May you succeed! 祝您成功！二.虛擬語氣在條

16、件從句中的用法。條件從句有兩類，一是真實條件句，另一是虛擬條件句。如 果假設(shè)的情況可能發(fā)生，是真實條件句，這種情況下謂語用 陳述語氣。如：If time p ermits, we 'lgo fishing together. 女果時間允許，我們就一起去釣魚。如果假設(shè)的情況是不存在的或不大可能發(fā)生的，則是虛擬條件句。如：If you had come yesterday, you would have met that famous professor.如果你昨天來，你就會見到那位著名的教 授了。(隱含的事實是：你昨天沒來，也沒見到那位著名教 授)。在含有虛擬條件句的復(fù)合句中，主從句的謂

17、語都要用虛擬語 氣，現(xiàn)將其形式列表如下： 動詞形式時間從句主句的過去式用過去分詞動詞原形與現(xiàn)在事實相反動詞過去式(be were)would(could/should/might)+ 動詞原形 與過去事實相反 had+動詞would(could/should/might)+have過去分詞與將來事實可能相反動詞過去式should+動詞原形 were to+ 動詞原形 would(could/should/might)+注：主句中的 should只用于第一人稱，但在美國英語中， should常被would代替；從句中的should可用于各種人稱。1.表示與現(xiàn)在事實相反的假設(shè)和結(jié)果。如:If I

18、were you, I should（would ,could, might）tell him如果她有the truth.要是我是你，我就會告訴他真相了。（事實上我 不是你）If she had time, she would（could, might）he Ip me.時間，她就會幫我了。（事實上她沒有時間）2表示與過去事實相反的假設(shè)和結(jié)果。如：If I had known your tele phone number yesterday, I如果昨天should（would, could, might）have tele phoned you.我知道了你的電話號碼，我就會給你打電話了。（事

19、實上我 昨天不知道你的電話號碼。）If you had taken my advice, you wouldn 'couldn ' have failed in the exam.如果你聽了我的建議，你就不會考試不及 格。（事實上你根本沒聽我的。3表示與將來事實可能相反的假設(shè)和結(jié)果。如:If it should rain, the crops would(could, might)be saved. 如天下雨，莊稼可能就收獲了。-What would happen if I put the paper on the fire?-It would burn.-我若把只放在火上會怎

20、么樣?-紙會燒著。were to + 動注：在表示與將來事實可能相反的條件從句中， 詞原形比較正式，常用于書面語中。如：If you were to go to Beijing, you would (could, might) have a chance to visit Tian An Men Square.三.虛擬語氣的其它用法。在 It is important (strange, natural, necessary)句型that”這類1虛擬語氣在主語從句中的用法。中的謂語動詞常用中，that所引導(dǎo)的主語從句（should）+動詞原形”結(jié)構(gòu)，表示某事是“重要”，“奇怪”， 然”，“必

21、要”等意義。如：It is imp ortant that every Beijinger (should) be able to speak English.重要的是每個北京人能說英語。It is necessary that he (should) be sent to hos pital at once.有必要馬上把他送醫(yī)院。2虛擬語氣在賓語從句中的用法。that。（1）在動詞wish后的賓語從句中，表示與現(xiàn)在或過去的事 實相反，或?qū)淼闹饔^愿望，從句通常省略連詞 a.表示對現(xiàn)在情況的虛擬：從句動詞用過去式或過去進(jìn)行式（be的過去式用were ）表示。如:I wish I knew t

22、he answer to the question.我希望知道這個問題的答案。（可惜不知道。）I wish it were sp ring in my hometown all the yeararound.但愿我的家鄉(xiāng)四季如春。（只是愿望，實際根本不可能實現(xiàn)。）b.表示對過去情況的虛擬：從句動詞用had+過去分詞。如:I wish (that) I hadn ' wasted so much time.我后悔不該浪費這么多時間。（實際上已經(jīng)浪費掉了。）He wishes （wished） he hadn 'lost the chance.他真希望沒有失去機(jī)會。（事實上機(jī)會已經(jīng)

23、失去了，他感到 惋惜。）c.表示對將來的主觀愿望：謂語動詞形式為would/should/could/might+動詞原形”，此時要注意，主句但愿雨能停止。我希望你安靜一些。的主語與從句的主語不能相同，因為主句的主語所期望的從 句動作能否實現(xiàn)，取決于從句主語的態(tài)度或意愿（非動作名 詞除外）。如：I wish you would be quiet.（2 ）在 suggest （建議） propose（建議）,insist （I wish it would sto p raining.,demand（要求）,order（命令）, 堅持要做），command（命令）,request（要求）,desi

24、re（希望）等動詞后的賓語從句中，謂語動 詞用（should）+動詞原形”，表示建議，要求，命令等。如：I suggest that we （should） start the meeting at once. 我建議 馬上開會。The undergraduate insisted that he (should) go to work in the south.這位即將畢業(yè)的學(xué)生堅持要到南方去工作。注:當(dāng) suggest 表示暗示，主語為 something ； insist 表示堅持觀點時，后接的賓語從句當(dāng)用真實語氣。比較：His silence suggested that he agr

25、eed with my decision.他的沉默暗示著他贊成我的決定。He suggested that I (should) stick to my decision.他建議我堅持自己的決定。He insists that doing morning exercises does good to peopie 'health.他堅持認(rèn)為做早操對健康有益。He insists that he (should) do morning exercises everyday.他堅持他每天都要早操3虛擬語氣在表語從句中的用法。當(dāng)主語為 advice, suggestion, order, p

26、roposal 等詞時后接 表語從句，表語從句中的謂語動詞常用“ (should)+動詞原形” 結(jié)構(gòu)，表示某人建議、勸告、命令等的內(nèi)容。如：My advice is that you should p ractise sp eaking English asoften as possible.我的建議是你盡可能經(jīng)常地練習(xí)說英語。The order from the commander was that the troops should set off for the front immediately.司令官的命令是部隊立即開拔去前線。4 .特殊的虛擬語氣結(jié)構(gòu)。(1)虛擬語氣用在狀語從句中由

27、as if或as ，though引導(dǎo)的狀語從句表示比較或方式時， 從句中的謂語動詞用虛擬語氣。動詞形式用動詞的過去式(bewere)或had+過去分詞。如：The teacher treats the student as if he were her ownchild.這位老師帶這位學(xué)生就象她的親生孩子一樣。He sp eaks as if he had been to the UnitedStates.他說得好象他真的到過美國似的。(2 )在 It is time (that) ；I' rather (that)句型中從句的謂語動詞常用動詞的過去式表示虛擬語氣，意思是“該干某事了，

28、時間已經(jīng)有些晚了”“我寧愿/希望”。如：It is time that we did something to stoppollution.該我們做些什么制止污染的時候了。It is time that Father pi cked up Lily from thekindergarten.該父親去幼兒園接莉莉的時候了。I' rather you told me the truth.我真希望你告訴我真相。I' rather I didn ' see you again. 我寧愿不再見著你。(3 )虛擬語氣用在簡單句中a情態(tài)動詞的過去式用于現(xiàn)在時態(tài)時，表示說話人的謙虛、

29、客氣、有禮貌、或委婉的語氣，常用于日常會話中。如：Would you be kind enough to show me the way to the postIt would be better for you not to stay up toolate .你最好別熬夜到很晚。b在一些習(xí)慣表達(dá)中office?請你告訴我去郵局的路好嗎？。如：You ' better set off now.你最好現(xiàn)在就出發(fā)。I' rather not tell you the secret.我情愿不告訴你這個秘密。c用 may+動詞原形”表示祝愿，但愿，此時may須置于句首(多用于正式文體中

30、)。如：May good luck be yours! 祝你好運！May you be happy! 祝你快樂！May you do even better! 祝你取得更大成就！用動詞原形。例如:Long live the people!人民萬歲！God bless you, ” said the priest.牧師說：“愿上帝保佑你！”5 .虛擬語氣在同位語從句中的用法在名詞 advice, suggestion, order, proposal 等后接的同位語 從句中，謂語動詞用虛擬語氣，起形式為（should）+動詞原形”，說明“建議”，“勸告”，“命令”等的具體內(nèi)容。如：The ord

31、er came that the work should be finished two days ahead of time.提前兩天完成工作的命令傳來了。Reluctantly she acce pted their propo sal that she should be op erated on.她勉強(qiáng)接受了他們要她去接受手術(shù)的建議。（一）主從句時間不一致情況下的虛擬語氣 （混合條件句）（二）有時條件從句中的動作和結(jié)果與主句中的動作，發(fā)生的時間不一致，這時動作的形式應(yīng)根據(jù)它所表示的時間加 以調(diào)整。如：If you had followed my advice, you would be

32、 able to finishthe work now.如果你當(dāng)時聽了我的話，現(xiàn)在就能完成這份工作了。（從句說明過去，主句說明現(xiàn)在。）If I were you, I would have gone to her birthdayparty.如果我是你，我就去參加她的生日晚會了。（從句說 明現(xiàn)在，主句說明過去。）If you hadn 'lent me some money, I couldn 'have bought the new house and most likely I would be still living in thedangerous house now.

33、 假若你不借錢給我，我不可能買下這幢新房，很可能現(xiàn)在還住在危房里。（從句 說明過去，主句說明過去和現(xiàn)在。）（二）含蓄條件句含蓄條件句大體有三種情況;非真實條件句中的條件從句有時不表出來，只暗含在上下文 中，這種句子叫做含蓄條件句。1.條件暗含在短語中。如： （1）W hat would I have done without you?without如沒有你，我會怎么辦呢？（條件暗含在分詞短語 you(2) It would be easier to do it this way.這樣做會比較容易。(條件暗含在不定式短語to do it this way（3）This same thing, h

34、app ening in wartime, would lead toa disaster.同樣的事，如發(fā)生在戰(zhàn)時，就會釀成大禍。（條件暗含在分詞短語 happ ening in wartime(4) But for your help we couldn 'have succeeded in the exp eriment.如果沒有你的幫助，我們的實驗是不會成功。(暗含條件是 but for your help) (5) He must have the strength of a hippopo tamus, or he never could have vanquished th

35、at great beast.他一定是力大如河馬，否則他絕不會擊敗那只龐大的野獸。(暗含條件是連詞 or) (6) Alone, he would have been terrified.是 alone)如是單獨一人，他是會感到害怕的。(暗含條件2.條件暗含在上下文中。如:(7) You might stay her forever. 能暗含 if you wanted你可以永遠(yuǎn)待在這兒。to)(8) We would have succeeded. 能暗含 if we had kept我們本來是會成功的。trying)(9) Your repu tation would be ruined.

36、(可能暗含if you你的名譽(yù)會敗壞的。should acce pt it)(10) I would app reciate a little of your time.謝謝你給我一點時間吧。(可能暗含if you were so kind as togive me a little ofyour time)3.在不少情況下，虛擬式已變成習(xí)慣說法，很難找出其暗含的條件。如：(11) You wouldn 'know.你不會知道。我愿意來。(12) I would like to come.(13) I wouldn 'have dreamed of it.這是我做夢也不會想到&

37、#39;的。(14) He told the story in such minute detail that he might himself have been an eye-witness.他將那事講的非常仔細(xì)，簡直就象他親眼看見一樣。（三）條件從句中省去if的情況if,將在if引導(dǎo)的表示虛擬的條件狀語從句中，?？梢允÷詇ad, were 或should提至句首。如：Had I seen the film, I would have discussed it with themlast night.假如我看了那部電影，昨晚我就可以和他們起討論了。C. wouldn ' helpD

38、. didn 'helpWere I a bird, I could fly freely.自由翱翔。假如我是一只小鳥，我就能Should it rain next week the farmers would have a goodharvest.要是下周能下雨的話，農(nóng)民們就能有個好收成了1 He suggested that the meetingput off.A. not beB. should notC. wouldn 'D. be not2 What would have happened if you A. hadn 'helpedB. couldn &#

39、39; helpher child?3 It is strange that heso.B. thinkA. thinksC. thoughtD. will thinkC. movesD.A or B4 If Iwith her last summer, Iwith her now.A. worked am getting on very wellB. had worked would get on very wellC. had worked would have got on very wellD. had worked will get on very well5 I wish Imy uncle yesterday.A. metB. have metC. would meetD. had met6 The old p rofessor gave orders that the exp erimentbefore 6.A. was finishedB. will finishC. be finishedD. shall be finished7 It 'high time hehome.A. goesB. wentC. will goD. is going to go8you succeed andyou be healthy.A. May may