《大学英语四级语法ppt课件.ppt》由会员分享，可在线阅读，更多相关《大学英语四级语法ppt课件.ppt（96页珍藏版）》请在三一办公上搜索。
1、大学英语四级-语法篇,王 颖,时态复习,时 态,时间状语从句当中的时态：一般过去时 所有的过去用一般现在时 表示 现在和将来现在完成时 现在完成和将来完成,非谓语动词,非谓语动词-不定式,1) 形式主动形式 被动形式一般式 to do to be done完成式 to have done to have been done进行式 to be doing 完成进行式 to have been doing,a) 完成式: 不定式的一般形式所表示的动作, 通常与主要谓语表示的动作(状态)同时(或几乎同时)发生, 或是在它之后发生. 假如不定式所表示的动作, 在谓语所表示的动作(状态)之前发生, 就要
2、用不定式的完成式.I am glad to have seen your mother (= I am glad I have seen your mother).(比较: I am glad to see you.)He is said to have written a new book about workers.He pretended not to have seen me.,b) 进行式: 如果主要谓语表示的动作(状态)发生时, 不定式表示的动作正在进行, 这时要用不定式的进行式.You are not supposed to be working. You havent quit
3、e recovered yet.We didnt expect you to be waiting for us here.He pretended to be listening attentively.,c) 完成进行式: 在谓语所表示的时间之前一直进行的动作, 就要用不定式的完成进行式.The struggle was known to have been going for twenty years.We are happy to have been working with you.,d) 被动式: 当不定式的逻辑上的主语是不定式所表示的动作的承受者时, 不定式一般要用被动形式.It
4、 is an honour for me to be asked to speak here.He wanted the letter to be typed at once.This is bound to be found out.There are a lot of things to be done.She was too young to be assigned such work.,2) 功用: 不定式可以作主语 (a), 宾语 (b), 表语 (c), 定语 (d) 或是状语 (e).a. To scold her would not be just.b. We are plan
5、ning to build a reservoir here.c. One of our main tasks now is to mechanize agriculture.d. Do you have anything to declare?e. We have come to learn from you.,3) 不带to 的不定式: a) 在“动词+ 宾语+不定式”结构中, 如果动词是表示感觉意义的see, hear, watch, smell, feel, notice等, 或是表示“致使”意义的 have, make, let等, 其后的不定式结构不带to.John made he
6、r tell him everything.这类结构转换为被动语态时, 后面的不带to 的不定式一般还原为带to 的不定式.She was made to tell him everything.,b) 在 had better, had best, would rather, would sooner, would just as soon, might (just) as well, cannot but 等搭配之后, 动词不定式也不带to.Id rather not have eggs and bacon for breakfast.They cannot but accept his
7、term.,c) 在make do, make believe, let drop, let fall, let fly, let slip, let drive, let go of, let there be, hear say, hear tell, leave go of等固定搭配中, 用不带to的动词不定式.John let fly a torrent of abuse at me.（一顿咒骂） Ive heard tell of him. （听说、听到）,d) 在动词help(或help +宾语)之后可用不带to的不定式, 也可用带to的不定式.Can I help (to) li
8、ft this heavy box? e) 在介词except, but 之后, 如果其前有动词do的某种形式, 不定式一般不带to, 反之带to.There is nothing to do except wait till it stops raining.Smith will do anything but work on a farm.Theres no choice but to wait till it stops raining.,f) 连词 rather than, sooner than 置于句首时, 其后的不定式不带to.Rather than push the book
9、back as he wanted to do, he forced himself to pick it up.出现在句中其他位置时, 其后的不定式有时带to, 有时不带to.He decided to write rather than telephone.The manager believes it is important to invest in new machinery rather than to increase wages.,g) 用作补语的动词不定式, 如果主语是由“all + 关系分句”，“thing +关系分句”，“what分句”或“thing +不定式结构”等构成
10、，并带有do的某种形式，这时，作为主语补语的不定式可以省to，也可以不省.What he will do is (to) spoil the whole thing.All you do now is complete the formThe only thing I can do now is go on by myself.The thing to do now is clear up this mess.The least I can do is drive everybody else closer to the issue.,4) 不定式的其他用法a) tooto 结构通常表示否定意
11、义:She was too young to understand all that.enoughto结构则表示肯定意义:She was not old enough to understand all that.not too, but too, all too, only too等和不定式连用时,不定式一般不表示否定意义:Hes only too pleased to help her.soas (to)这种结构也可用不定式作状语:Be so kind as to drop in some time when you are free.,b) 如果要说明不定是表示的动作是谁做的, 可以在不
12、定式前加一个for引起的短语:It is not hard for one to do a bit of good.It is a great honour for us to be present at this rally.在以某些形容词(如 kind, good, nice, wise, unwise, clever, silly, wrong, right, foolish, stupid, careless, considerate, rude, naughty, impolite等)作表语时, 不定式前可加一个of引起的短语, 来说明不定式指的是谁的情况:Its kind of y
13、ou to think so much of us.(It is) Awfully good of you to come and meet us.Its very nice of you to be so considerate.Its unwise of them to turn down the proposal.,动名词,具有动作性特征的名词1)是名词 seeing is believing2)具有动词性特征可以带宾语,一)动名词的形式:,一般形式：I dont like you smoking. 完成形式：I regret not having taken your advice.被
14、动形式：This question is far from being settled.,二) 动名词常考的点,1)动名词做主语谓语动词为单数2)在动名词和不定式中,做为介词的宾语是动名词3)动名词的否定直接在其前加否定词,通过代词的宾格或所有格形式给出逻辑主语.I would appreciate_ back this afternoon Ayou to call Byou call Cyou calling Dyoure calling（Key：C your calling 也对）I regret not having taken your advice.,4)有些词后只能接动名词,adm
15、it; appreciate; avoid; celebrate; consider; contemplate; defer; delay; deny; detest; discontinue; dislike; dispute; enjoy; it entails; escape; excuse; explain; fancy; feel like; finish; forgive; cant help; hinder; imagine; it involves; keep; it means; mention; mind; miss; it necessitates; pardon; po
16、stpone; practice; prevent; recall; report; resent; resist; risk; suggest; understand.,另外还有一些接-ing形式的常用说法,its no good; its no/little/hardly any/ use; its not/hardly/scarcely use; its worthwhile; spend money/time; theres no; theres no point in; theres nothing worse than; whats the use/point.,5 有些词后加不定
17、式和动名词均可,remember, forget, try, stop, go on, cease, mean后面用不定式和-ing形式，意义截然不容。I remembered to post the letters. (指未来/过去未来的动作)I remembered posting/having posting the letters (我记得这个动作)forgot与remember的用法类似。I regret to inform you that 我很遗憾地通知你I regretted having left the firm after twenty years. 为了二十年前的离开而
18、遗憾。,try to 努力 You really must try to overcome your shyness.try ing 试验 Try practicing five hours a day. I mean to go, but my father would not allow me to. 打算、想我想去，但我父亲不让我去。To raise wage means increasing purchasing power. 意味着赠加工资意味着增加购买力。,refer的用法：,我宁愿在这里等。I prefer to wait here. （所以啊，你不介意的话，我就等下去。）I p
19、refer waiting here.（我正在这里等，我就喜欢这么做。）I prefer swimming to cycling. （这个句子里面就不能用不定式了。）,分 词,3. 分词1) 意义: 过去分词通常来自及物动词, 带有被动意义和完成意义; 而现在分词有的来自及物动词, 有的来自不及物动词, 通常带有主动意义和未完成意义.frozen food a freezing winda bored traveller a boring journeya lost cause a losing battlea conquered army a conquering armya finishe
20、d article the last finishing touchthe spoken word a speaking birda closed shop the closing houra recorded talk a recording machine,来自不及物动词的过去分词很少能单独用作前置修饰语, 能作这样用的仅限于下面几个词, 仅表示完成意义, 不表示被动意义.the risen sun, fallen leaves, faded/withered flowers, returned students, retired workers, departed friends, es
21、caped prisoners, the vanished jewels, newly-arrived visitors 用作后置修饰语的过去分词一般都带有修饰语或其他成分, 在意义上相当于关系分句.Most of the people invited to the reception were old friends.,2) 句法作用a) 作定语: distinguished guest 贵宾, unknown heroes 无名英雄, armed forces武装部队, canned food罐头食品, boiled water开水, steamed bread馒头, stricken a
22、rea灾区分词还可构成合成词作定语: simply-furnished room陈设简单的房间, clear-cut answer明确的答复, highly-developed industry高度发展的工业, heartfelt thanks衷心的感谢, hand-made goods手工制品, man-made satellite人造卫星,b) 作补足语: 可以带过去分词作宾语补足语的动词有:see, hear, feel, find, think等表示感觉和心理状态的动词.I saw the students assembled in the hall.We found her grea
23、tly changed.make, get, have, keep等表示”致使”意义的动词:I have my hair cut every ten days.She got her bad tooth pulled out.Please keep us informed of the latest developments.like, want, wish, order等表示希望, 要求, 命令等意义的动词:I dont want any of you (to be) involved in the scandal.He wont like such questions (to be) di
24、scussed at the meeting.,c) 过去分词短语常用作状语, 修饰谓语, 很多都说明动作发生的背景或情况.Guided by these principles, they went on with the work,Delighted with her work, they made her the general manager.过去分词短语也可作状语表示原因, 相当于一个表示原因的状语从句.Influenced by his example, they performed countless good deeds.有时也可说明动作发生的时间, 相当于一个表示时间的状语从句
25、.This method, tried in areas near Shanghai, resulted in a marked rise in total production.间或也可表示一个假设的情况, 相当于一个条件从句.Given closer analysis, we can see this is totally wrong.偶尔也可用来代替一个“让步”状语从句.Picked 20 years a year, it grows tired only after 40 or 50 years.,2022/12/28,虚拟语气,条件句,三种基本形式,If I had a bike,
26、I would lend it to you.(if从句用过去时, 主句用should/ would/ could/ might+不定式)If he had been here, he would have helped you.(从句过去完成时, 主句should /would/ could/ might +不定式完成时)If I should/were to do the experiment, I would do it some other way. (从句用should/ were to, 主句用should/would /could /might+不定式),if的省略,1. Wer
27、e you in my position,you would do the same.2. Had he come earlier,he would have seen her.3. Should they attack us, we would wipe them out completely.,If only,If only you would listen to reason.If only I were ten years younger.IF only he didnt drive so fast.If only he had asked someones advice.If I c
28、ould only go to the concert.If I could only/but/just explain.,I wish,I wish I knew the answer.I wish I had known the address.I wish I were young.I wish you would stop asking silly questions.I wished I knew his address.(发生在过去=I was sorry I didnt know his address.)I wished I were young.(=I was sorry I
29、 was not young.),Would rather,I would rather you told her the truth.Id rather you came tomorrow.Id rather (that) he painted it blue.I would (just)as soon that John had not spoken rudely to me.,It is (high) time that.,It is time we_(leave).It is time we _(go)to bed.Its high time that you were in bed.
30、Its about time we left.,Its important that.,It is important that we _ (speak) politely.It is imperative that we_ (practice) criticism and self-criticism strange, advisable, anxious, crucial, appropriate compulsory, desirable, eager, essential, fitting, imperative(绝对必要的), impossible, improper, natura
31、l, necessary, obligatory, preferable, proper, urgent, vital, willing,I insist that,I insist that we _ (go) there by bus.He suggested that we _ (leave) early.The judge ordered that the prisoner _ (be) sentenced to 30 days in jail.,这些动词和名词后的从句为should+V,advise(advice), agree(agreement), decide(decision
32、), decree, demand, determine (determination), grant, indicate(indication), insist, move (insistence), order, request, require prefer(preference), urge, vote, ask, propose(proposal), (requirement), resolve(resolution), stipulate, desire(stipulation), allow, arrange, beg, concede, demonstrate, ensure,
33、 pray, intend, move, pledge, command,My suggestion.,My suggestion is that we should tell him.Our only request is that this should be settled as soon as possible.request command necessity importance motion proposal resolution recommendation understanding,but for, otherwise, without,The storm delayed
34、us. But for the storm we would have been in time.I used my calculator; otherwise Id have taken much longer.Supposing I accepted this offer, what would you say?Without you timely help, my daughter would have drowned.,情态动词,情态动词（model verb）用来表示能力、允许、可能、必须、劝告、意愿等概念或态度。主要的情态动词有can （could），may （might），sha
35、ll （should），will （would），must，ought to，need，dare等。情态动词没有人称和数的变化，其后常跟不带to的不定式。,1. 情态动词的一般用法：,(1) 表示能力: can, could, be able toHe is over 80 but still can read without glasses.She couldnt come yesterday.He cant come tomorrow.,can/could 与be able to 用法比较1）be able to 除有一般现在时、一般过去时、一般将来时外，还可有现在完成时、不定式、动词-i
36、ng 形式等。 This is the information Ive been able to get so far. To be able to ride a bike, she practiced a lot. Just being able to drive a horse, a cart isnt much help to us. 2) could表示过去总的、经常性的能力；was/were able to 表示过去具体情况下具有的能力，并且做了某动作。He could speak French, so he was able to show the French lady the
37、way. 3) 表示将来的能力常用will be able to.When will you be able to take us to town?,(2) 表示许可：can/could, may/might; cant, may not, mustnt, must not,1) 征询“许可”或给予“许可”可用can/could 或may/might 表示。May 用于正式场合，can 用于非正式场合，could 用于客气的询问，might 极少用。 You can go at four oclock. Could I borrow your pen? Students may take 3
38、books each. Might I ask whether you are using the typewriter? 2) 表示“不允许”用 cant, may not, mustnt； must not 语气重。 You cant leave the table unless you finish your meal. Put that cigarette out. You must not smoke near a petrol pump! 3) 表示过去“许可”不用could，might，要用其他表达方式。 We had been/were given permission to
39、speak to the patient. 但在间接引语中表达过去“许可”，可用could，might。 The nurse said that we could/might speak to the patient for just a few minutes.,(3) 表示可能性：may/might, can/could, must; cant,1）may, might 用来推测现在“可能”；may比might表示的可能性大些。Why isnt John in class? He may/might be sick. maybe是副词，不是情态动词。Maybe he is sick. 2)
40、 在日常口语中常用can/could 表示“可能”。 You can/could walk for miles in the country without meeting anyone. Can the news be true? No, it cant be true.3) must表示可能性最大，“必定”；否定形式用cant表示“肯定不”、“必定不会”。You must be hungry after a long walk.The phone is ringing, but there is no answer. She cant be at home.,（4）表示必须和需要：must
41、, have to, need,1）must表示说话人认为“必须”；否定回答时用neednt “不必”。You must be here at nine oclock.Must you go soon? No, I neednt go yet.2) have to 表示他人或客观情况要求“必须”。 I have to be back at school by eight. I have a lot of work to do tonight. We dont have to wear uniforms in school.l 口语中常用have got to 表示“必须”。I have got
42、 to leave now. I have a meeting in ten minutes.,3) need 表示动作者“需要”、“有必要”，用于否定句或疑问句；肯定回答用must，否定回答用neednt。 Need he go now? Yes, he must. No he neednt.l need 常用作实义动词。 You need to learn the value of time. You didnt need to tell him the news. Does she need to go?,（5）表示责任和劝告: should, ought to, must, had b
43、etter,1)用should和ought to 表示责任和劝告，后者的语气重些You should/ought to do as you are told.Such things shouldnt/ought not to be allowed.2)有时也用must 表示责任和劝告。You must see the movie. Its wonderful.3) 口语中也常用had better 表示劝告，意为“最好做/不做某事”。You had better take care of yourself.Youd better not make a mistake next time.Had
44、nt you better see who is at the door?,（6）表示建议：shall，may/might as well, may/might just as well,1) “shall I/we” 表示征求对方对建议的看法。Shall we carry the boxes into the house?Lets go, shall we?2) may/might as well, may/might just as well 表示推荐更佳方案，建议另一种做法，意为“倒不如”，“不也一样吗？”。We may as well stay here tonight.You mig
45、ht just as well tell the truth.,(7) 表示许诺：shall,shall用于第二、三人称，表示说话人的许诺。 You shall have your money back next week. If he passes the exam, he shall have a holiday.,(8) 表示意愿：shall, will/would,1) you/he/they shall 表示说话人的强烈意愿，甚至威胁。You shall pay for this.They shall do what I tell them to do.l 在法律条文、规章制度中，s
46、hall 表示“必须”。Each competitor shall wear a number.,2) will/would 表示动作者愿意。I will lend you the book if you need it.I wont do it again.I have been trying to open the door, but the key wont turn.l “will you/would you” 在下列句中表示客气的建议、询问。Will you please have a drink?Would you please pass me the salt?Would you
47、 like a cup of tea?Would you mind if I opened the window?Would you mind opening the window? Would you mind my opening the window?l would 还表示过去的习惯。等于used toOn Sundays he would get up early and go fishing.,(9)表示勇敢：dare,dare 表示“敢于”，用于否定句、疑问句或条件句。He dare not try.How dare you open the letter?If you dare
48、say a word, Ill strike you down.l dare 还常用作实义动词。He dare to surf in heavy waters. l daresay 或 dare say，表示probably, I suppose.I dare say he will come home late.,2. 情态动词的特殊用法,（1） 情态动词+不定式完成时1） can/could, may/might, must + have + 动词的过去分词用于肯定句：表示对过去事件的主观判断，推测过去某动作“可能”、“也许”、“一定”已发生。Tom could have taken th
49、e dictionary. I saw him using it last Sunday.I cant find my sunglasses. I may/might have left them at the restaurant yesterday.You screamed in your sleep last night. You must have had a terrible dream.用于否定句：表示推测过去某动作“可能”、“也许”、“一定”没有发生。She couldnt have finished her work so soon.She may not have seen
50、you.Dad mustnt have washed the dishes last night.,2) should/ought to + have + 动词的过去分词。用于肯定句：评论过去“应该做”而实际并未做的动作，意为“本应该”。I didnt ask her. Its a pity. You should have asked her. You ought to have asked everyone.用于否定句：评论过去“不应该做”而实际做了的动作，意为“本不应该”。I only told Mike. You shouldnt have told anyone. You ought
