动词不定式的简介

1、动词不定式的简介动词不定式是一种非限定性动词，由to+动词原形构成，但在有些情况下to可以省略。它还是属于动词，本身可以带宾语和状语。动词不定式在句中可以作主语、宾语、表语、定语和状语，还可用在复合结构中，而且有完成式、进行式、完成进行式和否定形式。动词不定式的被动形式除了一般形式外还有其完成式和进行式。动词不定式的时态、语态动词不定式可以作以上各种成分，但它毕竟是动词，所以有动词的属性动词不定式及其短语还可以有自己的宾语、状语，虽然动词不定式在语法上没有表面上的直接主语，但它表达的意义是动作，这 一动作一定由使动者发出。这一使动者我们称之为 逻辑主语，其形式如下： 主动形式被动形式一般式（n

2、ot）to make （ not）to be made完成式（not）to have made （not） to have been made进行式（not）to be making完成进行式 （not） to have been making（1）语态 如果动词不定式的逻辑主语是这个不定式所表示的动作的承受者，不定式一般要用被动语态形式。如：It's a great honour to be invited to Mary's birthday party. （不定式作主语）It was impossible for lost time to be made up. （不定式

3、作主语）I wish to be sent to work in the country. （不定式作宾语）Can you tell me which is the car to be repaired? （不定式作定语）He went to the hospital to be examined. （不定式作状语）在 There be 结构中，修饰主语的不定式可用被动，也可用主动。女口： There are still many things to t ake care of（ to be taken careof）.但有时两种形式表达的意思不同，如： These is nothing to

4、 do now. （ We have nothing to do now. ） There is nothing to be done now. （We can do nothing now. ）（2）时态1）现在时：一般现在时表示的动词，有时与谓语动词表示的动作同时发生，有时发生在谓语动词的动作之后。He seems to know this.I hope to see you again. = I hope that I'll see you again. 我希望再见到你。2）完成时：表示的动作发生在谓语动词表示的动作之前。I'm sorry to have given y

5、ou so much trouble.He seems to have caught a cold.3）进行时： 表示动作正在进行，与谓语动词表示的动作同时发生。He seems to be eating something.4）完成进行时：She is known to have been wreaking on the problem for many years.疑问词不定式结构疑问词 who,what,which,when,where,whether,how 后可接不定式构成不定式短语，在句中作主语、宾语、表 语等。如： When to leave for London has not

6、 been decided yet.（不定式在句子中做主语） Mr. Smith didn't know whether to leave or stay there.（不定式在句子中做宾语） I asked Professor Xu how to learn English well. （不定式在句子中做间接宾语） The question was where to get the medicine needed. （不定式在句子中表语）以上例句中疑问词+不定式部分，均可转换为相应的从句形式。如：When we shall leave ？ howcould learn 经常在这种结构

7、中使用的动词有： consider,decide,discover,explain,find out,forget,hear,know,lea rn,observe,understand,wonder等。 动词不定式的语法功能一、作宾语1）动词+不定式afford.aim.appear.agree.arra nge .ask .be .decide. bother.care.choose . come.dare.dema nd.desire.determ ine .expect.elect.en deavor .hope.fail.happe n . help .hesitateear n .

8、Ion g .mean.man age.offer.ought.pla n . prepare.prete mise. refuse. seemtend.wait .wish.un dertake.举例:The driver failed to see the other car in time.司机没能及时看见另一辆车。I happe n to know the an swer to your questi on.我碰巧知道你那道问题的答案。2）动词+不定式；动词+宾语+不定式ask, beg, choose, expect , hate, help intend like, l

9、ove, n eed prefer, prepare, promise, want, wishI like to keep everythi ng tidy.我喜欢每件东西都保持整洁。I like you to keep everyth ing tidy.我喜欢你年使每件东西都保持整洁。I want to speak to Tom. 我想和汤姆谈话。I want you to speak to Tom.我想让你和汤姆谈话。3）动词+疑问词+ todecide, know, consider forget, learn, remember, show, understand, see, wond

10、er, hear, find out, explain, tell Please show us how to do that.请演示给我们如何去做。There are so many kinds of tape-recorders on sale that I can't make up my mi nd which to buy.有这么多的录音机，我都拿不定主意买哪一种。注意:疑问词带不定式在句中作成分时，谓语动词用单数。The questi on is how to put it into practice.问题是怎样把它付诸实施。4）以下动词后，只能跟不定式作宾语。女口：agr

11、ee,ask,aim,arra nge,choose,decide,dema nd,expect,fail ,help,hope,lea n,lo ng,ma nage,offer,pla n,prepare, prete nd,promise,refuse,wish等，这些词大部分可接th at引导的从句。如：I decided to ask for my money back.I decided that I would ask for my money back.When our visit to the farm was over,we expected to startback on

12、 foot.When our visit to the farm was over, we expected that wewould start back on foot.5） 当复合宾语中的宾语是不定式时，先用形式宾语it代替不定式，把不定式置于补语之后，即：主语+动词+ it +补语+ to do句式。 女口：We think it quite important for us to learn a foreignlanguage well.He feels it his duty to help the poor.二、作补语1）动词+宾语+不定式（to do）adviseallowap

13、po intbelievecausechalle ngecomma ndcompelcon siderdeclaredriveen ableen couragefindforbidforceguesshireimagi neimpelin duceinformin structin vitejudgeknowlikeorderpermitpersuaderemi ndreportrequestrequireselect sendstatesupposetellthi nk traintrustun dersta ndurgewarn例句：a. Father will not allow us

14、to play on the street.父亲不让我们在街上玩耍。b. We believe him to be guilty.我们相信他是有罪的。to 的动词不定式。 find 后也可带一个从句。此类动词还 有 get ，Find 后可用分词做宾补，或先加形式宾语，再加形容词，最后加带 have 。I found him lying on the ground.I found it important to learn.I found that to learn English is important.典型例题 :The next morning she found the man _

15、in bed ， dead.A. lying B. lie C. lay D. laying答案： A.find 的宾语后面，用分词或分词短语，起宾语补足语作用。现在分词表达主动，也表达正在进行，过去分词表达被动。2）to + be 的不定式结构，作补语的动词。Acknowledge, believe, consider, think,declare （声称）,discover, fancy （设想），feel find, guess, judge,imagine,know, prove,see（ 理解） , show,suppose,take （以为 ） , understandWe con

16、sider Tom to be one of the best students in our class. 我们认为汤姆是班上最好的学生之一。 典型例题Charles Babbage is generally considered _ the first computer.A. to invent B. inventing C. to have invented D. having invented答案：A.由consider to dosth.排除B、D。.此句只说明发明这一个事实，不定式后用原形即可。而C为现在完成时，发明为点动词一般不用完成时，且此处也不强调对现在的影响，因此不选 C。

17、3）to be + 形容词Seem,appear, be said, be supposed, be believed, be thought, be known, be reported, hope, wish,desire, want,plan, expect,mean ?The book is believed to be uninteresting. 人们认为这本书没什么意思。4）there be+ 不定式believe, expect, intend, like, love, mean, prefer, want, wish, undrstandWe didn't expec

18、t there to be so many people there 我们没料到会有那么多人在哪里。 有些动词需用 as 短语做补语，如 regard, think believe, take, consider.We regard Tom as our best teacher. 我们认为汤姆是我们最好的老师。Mary took him as her father . 玛丽把他当作自己的父亲。三、作主语 动词不定式作主语时，句子的谓语动词常用单数，其位置有以下两种：（ 1）把不定式置于句首。 如：To get there by bike will take us half an hour.（

19、 2） 用 it 作形式主语，把真正的主语不定式置于句后，常用于下列句式中 。如： It + be+名词 + to doIt's our duty to take good care of the old. It takes sb+some time+to doHow long did it take you to finish the work? It +be + 形容词 + for sb + to doIt is difficult for us to finish writing the compositionin a quarter of an hour. It +be + 形

20、容词 + of sb + to doIt is stupid of you to write down everything the teachersays. It seems ( appears ) + 形容词 + to do It seemed impossible to save money.在句型中，常用表示客观情况的形容词，如：difficult,easy,hard,importa nt,impossible ,n ecessary等；在句型中，常用careless,clever,good,foolish,honest,kind,lazy,nice,right,silly,stupi

21、d,wise 等 表示赞扬或批评的词。在不定式前的 sb, 可看作其逻辑主 语。这 一句式有时相当于Sb is + 形容词 + to do 句式，如口 ： It'skind of you to help me with my English.= You are kind to helpme with myEnglish.（3）举例1）It's easy （for me ） to do that . 我做这事太容易了easy, difficult, hard, important, possible, impossible, comfortable, necessary, bet

22、ter;the first, the next, the last, the best, too much, too little, not enoughIt's so nice to hear your voice.听到你的声音真高兴。It's necessary for you to lock the car when you do not use it.当你不用车的时候，锁车是有必要的。2）It's very kind of you to help us. 他帮助我们，他真好。Kind, nice, stupid, rude, clever, foolish, t

23、houghtful, thoughtless, brave, considerate（考虑周至 U 的 ）,silly, selfish （自 私的 ） 例句 :It was silly of us to believe him. 我们真愚蠢，竟然相信了他。It seemed selfish of him not to give them anything. 他不给他们任何东西，这显得太自私了。注意： 1）其他系动词如， look, appear 等也可用于此句型2）不定式作为句子成分时，动词用单数形式。3）当不定式作主语的句子中又有一个不定式作表语时，不能用 It isto的句型（ 对） T

24、o see is to believe. 百闻不如一见。（错） It is to believe to see.四、作表语 不定式作表语表示具体动作或将来动作；动名词作表语表示抽象的一般行为。 To be kind to the enemy is to be cruel to the people. My chief purpose is to point out the difficulties ofthe matter. What I would suggest is to put off the meeting.当主语和表语都是不定式时，其含义一是条件，一是结果（例）。当主语是 aim,

25、duty,hope,idea,mista ke,pla n,purpose,suggesti on等为中心词的名词词组（例）时，或以what引导的名词性分句（例），不定式说明主语的内容。 Our work is serving the people. What he likes is taking a walk after supper. The story told by Mr.Wang is interesting.句动名词作表语，与主语部分可以转换，如Servi ng thepeople is out work,而句中是现在分词作表语，说明主语的性质、状态，现在分词具有形容词的各种特征，

26、另外，动名词作表语还应与进行时态区别开来。五、作定语1. 不定式作定语不定式在句中作定语，置于被修饰的名词或代词之后。如： The next train to arrive is from Washington. Have you anything to be taken to your sister? Do you have anything to say on the question? Would you please give me some paper to write on? My wish to visit France has come true at last.不定式短语作定

27、语和被修饰词之间表示以下关系：（1）表示将来的动作 （例 ） 。(2) 与被修饰词之间有动宾关系，如是不及物动词，则需加介词(例)。尽管有被动含义，却仍用主动语态 (例)；(3) 与被修饰词之间有动宾关系，同时与句中其它词之间又有逻辑上的主谓关系时，(例)。to arrive=that will arrive 。如只有动宾关系，而无逻辑上的主谓关系，则需用被动语态(4) 不定式作定语时，一般可转换为定语从句，例六、作状语1 )目的状语To only to (仅仅为了 ), in order to, so as to, so(such) as to 女吐止匕 以便.)He ran so fast

28、 as to catch the first bus. 他飞快地跑以便赶上第一班车。I come here only to say good-bye to you. 我来仅仅是向你告别。2) 作结果状语，表事先没有预料到的，要放在句子后面。What have I said to make you angry.He searched the room only to find nothing.3) 表原因I'm glad to see you.典型例题The chair looks rather hard, but in fact it is very comfortable to _.

29、"形容词 +动词不定式 "结构的末尾A. sit B. sit on C. be seat D. be sat on答案： B. 如果不定式为不及物动词，其后应有必要的介词。当动词与介词连用时，常位于 省 to 的动词不定式1) 情态动词 ( 除 ought 外， ought to) ：2) 使役动词 let, have, make ：3) 感官动词 see, watch, look at, notice , observe, hear, listen to, smell, feel, find 等后作宾补，省略 to。注意：在被动语态中则 to 不能省掉。I saw hi

30、m dance.=He was seen to dance.The boss made them work the whole night.=They were made to work the whole night.4) would rather ， had better ：5) Why / why not ?6) help 可带 to，也可不带 to, help sb (to) do sth7) but 和 except： but 前是动词 do 时，后面出现的动词用不带 to 的动词 不定式。8) 由 and, or 和 than 连接的两个不定式，第二个 to 可以省去：9) 通常在

31、 discover, imagine, suppose, think, understand 等词后，可以省去 to be:He is supposed (to be) nice. 他应该是个好人。举例:He wants to move to France and marry the girl.He wants to do nothing but go out.比较:He wants to do nothing but go out.He wants to believe anything but to take the medicine.典型例题1) - I usually go there

32、 by train.- Why not _ by boat for a change?A. to try going B. trying to go C. to try and go D. try going 答案： D. why not 后面接不带 to 的不定式，因此选 D 。2) Paul doesn't have to be made _. He always works hard.动词不定式的否定式Tell him not to shut the win dowShe pretended not to see me when I passed by. 我走过的时候，她假装没看

33、见。 典型例题1) Tell him _ the window.A. to shut not B. not to shut C. to not shutD. not shut 答案： B。 tell sb to do sth 的否定形式为 tell sb not to do sth.2) She pretended _ me when I passed by.A. not to see B. not seeing C. to not seeD. having not seen 答案： A。 pretend 后应接不定式。其否定形式为 pretend not to do sth. 。3) Mrs

34、. Smith warned her daughter _ after drinking.A. never to drive B. to never driverC. never driving D. never drive答案： A。 warn sb to do sth. 的否定形式为 warn sb not to do sth. 此处用的是否定词 never.4) The boy wanted to ride his bicycle in the street ， but his mother told him _.A. not to B. not to do C. not do itD.

35、 do not to答案：A o not to为not to do it的省略形式。可以只用to这个词，而不必重复整个不定式词组。及物动词do后应有名词、代词等，否则不对，因此 B， D 不对。5) The patient was warned _ oily food after the operation.A. to eat no B. eating not C. not to eatD. not eating答案： Co warn 一词要求后用不定式，此处为不定式的被动，否定形式为 be warned not to do o不定式的特殊句型1、不定式的特殊句型 so as to1) 表示目

36、的；它的否定式是 so as not to do oTom kept quiet about the accide nt so as not to lose his job.汤姆对事故保持沉默是为了不丢掉他的工作。Go in quietly so as not to wake the baby.轻点进去，别惊醒了婴儿。2) so kind as to - 劳驾Would you be so kind as to tell me the time?劳驾，现在几点了。2、"Why not +动词原形"表达向某人提出建议 "为什么不 ?""干吗不?&

37、quot;例如：Why not take a holiday? 干吗不去度假 ?3、It's for sb. 和 It's of sb.1) for sb. 常用于表示事物的特征特点，表示客观形式的形容词，如easy, hard, difficult, interesting, impossible 等：It's very hard for him to study two Ian guages.对他来说学两门外语是很难的。2) of sb 的句型一般用表示人物的性格，品德，表示主观感情或态度的形容词，如good, kind, nice, clever, foolish

38、, right oIt's very nice of you to help me. 你来帮助我，你真是太好了。for 与 of 的辨别方法：用介词后面的代词作主语，用介词前边的形容词作表语，造个句子。如果道理上通顺用of，不通则用for。如：You are nice. （ 通顺，所以应用 of） 。He is hard. （人是困难的，不通，因此应用 for。）4、不定式的特殊句型tooto1） tooto太以至于He is too excited to speak. 他太激动了，说不出话来。- Can I help you ? 需要我帮忙吗 ?- Well, I'm afr

39、aid the box is too heavy for you to carry it, but thank you all the same.不用了。这箱子太重，恐怕你搬不动。谢 谢您。2） 如在 too 前有否定词，则整个句子用否定词表达肯定， too 后那个词表达一种委婉含义，意为"不太"。It's never too late to mend.（ 谚语 ）改过不嫌晚。3）当 too 前面有 only, all, but 时，意思是：非常 等于 very 。I'm only too pleased to be able to help you. 我非

40、常高兴能帮助你。He was but too eager to get home. 他非常想回家。动词不定式的 "to" 与介词的 "to" 区别 to 有两种用法：一为不定式 +动词原形；一为介词 +名词/动名词 , to 在下面的用法中是第二种，即 to+ 名词/动名词：admit to 承认， confess to 承认， be accustomed to 习惯于， be used to 习惯于， stick to 坚持， turn to 开始，着手于， devote oneself to 献身于， be devoted to 致力于， look

41、forward to 盼望， pay attention to 注意介词 but,except,besides+to do （do）在这种句型中，如介词前有动词do,后面应接不带to的不定式；如无do，则接to不定式，即带do不带to,带to不带do。如：The enemy soldiers had no choice but to give in.On Sunday afternoon I had nothing to do but watch TV.动词不定式与动名词区别与联系1）动名词与不定式的区别：动名词表达的是： 状态，性质，心境，抽象，经常性，已发生的 不定式表达的是： 目的，结果

42、，原因，具体，一次性，将发 生的2）接不定式或动名词，意义相同。3）在下列情况下，一般要用不定式： hate,like,love 前有 would （should ） 时，如： rd like to have a cup of coffee. 当谓语动词 begin,continue,start 等是进行式时，如： Thestudents are starting to work on the di fficult maths problem. begin,continue,start 与 know,understand 等状态动词连用时，如： I soon began to understa

43、nd what was happening.4. advise,allow,encourage,forbid,permit 等动词后接动名词作宾语，或带不定式作宾语补足语。如：Our teachers don't permit our swimming in the lake.Our teachers don't permit us to swim in the lake.4）部分动词后接不定式或动名词时，意义差别较大，应根据句子语境选择使用 forget,remember,regret 后接不定式，表示现在或未来的动作，接动名词表示动作已经发生。如：Don't for

44、get fo post the letter for me.Have you forgotten meeting her in Beijing Airport?Remember to close the windows before you leave.I remember writing him a letter a year ago.We regret to tell you that all of you are not invited toattend the meeting. They regretted ordering these books from abroad.动名词与不定

45、式语义不同的有1 stop to do2 forget to do3 remember to do4 regret to do5 cease to do6 try to do7 go on to do8 afraid to do9 interested to do10 mean to do11 begin/ start to do1 forget doing/to do11 组： stop doing forget doing remember doing regret doing cease doing try doing go on doing afraid doing intereste

46、d doing mean doing begin/ start doingforget to do 忘记要去做某事。 （未做） forget doing 忘记做过某事。 （已办公室的灯还在亮着，它忘记关了。The light in the office is stil on. He forgot to turn it off. 没有做关灯的动作 ）He forgot turning the light off.他忘记他已经关了灯了。已做过关灯的动作 ）Don't forget to come tomorrow. 别忘了明天来。（to come 动作未做 ）典型例题- The light

47、 in the office is still on.- Oh， I forgotA. turning it off it offB. turn it offC. to turn it off D. having turned答案： C 。由而 forget doing sththe light is still on 表示灯已经关上了，可知灯亮着，即关灯的动作没有发生，因此用而自己忘记了这一事实。此处不符合题意。forget to do sth.2 stop doing/to dostop to do 停止，中断做某事后去做另一件事。 stop doing 停止做某 事。They stop

48、to smoke a cigarette. 他们停下来，抽了根烟。 I must stop smoking.我必须戒烟了。She reached the top of the hill and stopped _ on a big rock by the side of the path.A. to have rested B. resting C. to rest D. rest答案： C 。由题意可知，她到了山顶，停下来在一个路边的大石头上休息。因此，应选择停下来 "stop to do sth.去做另一件事 " 。而不仅仅是爬山动作的终止，所以 stop doing

49、sth. 不正确。3 remember doing/to doremember to do 记得去做某事 （ 未做 ）remember doing 记得做过某事 （ 已做 ）Remember to go to the post office after school.记着放学后去趟邮局。Don't you remember seeing the man before?你不记得以前见过那个人吗 ?4 regret doing/to doregret to do 对要做的事遗憾。（ 未做）regret doing 对做过的事遗憾、后悔。（ 已做）I regret to have to do

50、 this, but I have no choice.我很遗憾必须这样去做，我实在没有办法。I don't regret telling her what I thought.我不为告诉她我的想法而后悔。典型例题-You were brave enough to raise objections at the meeting.-Well, now I regret _ that.A. to do B. to be doing C. to have done D. having done答案： D 。 regret having done sth. 对已发生的事感到遗憾。 regret

51、 to do sth. 对将要做的事感到遗憾。本题为对已说的话感到后悔，因此选D。5 cease doing/to docease to do 长时间，甚至永远停做某事。cease doing 短时停止做某事，以后还会接着做。That department has ceased to exist forever.那个部门已不复存在。The girls ceased chatting for a moment when their teacher passed by.姑娘们在老师走过时，停了会聊天。6 try doing/to dotry to do 努力，企图做某事。try doing 试验，

52、试着做某事。You must try to be more careful.你可要多加小心。I tried gardening but didn't succeed.我试着种果木花卉，但未成功。7 go on doing/to dogo on to do 做了一件事后，接着做另一件事。go on doing 继续做原来做的事。After he had finished his maths ， he went on to do his physics. 做完数学后，他接着去做物理。Go on doing the other exercise after you have finished this one.作完这个练习后，接着做其他的练习8 be afra