英语不定式

概念：动词不定式

一．动词不定式由to+动词原形构成。这里的to是不定式标志，没有词义。不定式具有名词、形容词或副词的某些语法功能，又有动词的时态和语态的特点及作用。可以做主语、宾语、宾语补足语、表语、定语、状语。

二．动词不定式的形式和时态

动词不定式是非谓语动词的一种，由不定式符号(to)加动词原形构成。不定式的形式有五种：1．一般式to do

例如：I like to read English.

2．进行式to be doing

例如：He seemed to be reading something at that time.

3．完成式to have done

例如：He seemed to have cleaned the room.

4．被动式to be done

例如：The work is to be done soon.

5．完成被动式to have been done

例如：The boy is said to have been sent to hospital yesterday.

6.。否定形式not to do

例如：He asked me not to make such a mistake.

三．.动词不定式与疑问词连用

疑问代词who, what, which和疑问副词when, where, how, why等后面可以接动词不定式，构成动词不定式短语，可以在句子中作主语、宾语、表语等成分。

例如：(1) He doesn’t know how to use the machine.（不定式作宾语）

(2) How to use the machine is a question. （不定式作主语）注意:疑问词带不定式在句中作主语时，谓语动词用单数。

(3) The question is when to go there. （不定式作表语）

一、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.

(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：

①It＋be＋名词＋to do

It's our duty to take good care of the old.

②It takes sb+some time+to do

How long did it take you to finish the work?

③It＋be＋形容词＋for sb＋to do

It is difficult for us to finish for swriting the composition in a quarter of an hour.

在句型③中，常用表示客观情况的形容词，如：

easy,difficult,hard,important,possible,impossible,comfortable,necessary,better;

④It＋be＋形容词＋of sb＋to do

It is stupid of you to write down everything the teacher says.

在句型④中，常用careless,clever,good,foolish,honest,kind,lazy,nice,right,silly,stupid,wise rude, clever,foolish,thoughtful,thoughtless（欠考虑的；不考虑的）,brave,considerate(考虑周到的),selfish(自私的)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：It's kind of you to help me with my English.=You are kind to help me with my English.

⑤It seems(appears)＋形容词＋to do

It seemed impossible to save money.

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) 不定式作为句子主语时，动词用单数形式。

对应性：To see is to believe.百闻不如一见。

二．不定式作表语

1)不定式作表语一般表示具体动作，特别是表示将来的动作。

To do two things at a time is to do neither．--次做两件事等于未做。

What I would suggest is to start work at once.我的建议是立刻开始干。

2）如果主语是不定式（表示条件），表语也是不定式（表示结果）。

To see is to believe.百闻不如一见。

To work means to earn a living．工作就是为了生活。

3)如果主语是以aim，duty，hope，idea，happiness，job，plan，problem，purpose，thing，wish等为中心的名词，或以what引导的名词性从句，不定式作表语是对主语起补充说明作用。His wish is to buy a luxurious car in the near future．他的希望是在不远的将来买一辆豪华轿车。What Iwant to say is to start tomorrow morning.我的建议是立刻开始干。

The question is how to put it into practice.

问题是怎样把它付诸实施。(含有疑问词的不定式作表语)

三．作宾语

1 以下动词后，只能跟不定式作宾语

1）afford （付得起），agree（同意），aim(力求做到), appear（显得），arrange（安排），ask（要求），attempt （试图），care（想要），choose（决定），claim（声称），condescend（屈尊），consent （准许），decide（决定），demand（要求），determine（决心），endeavor（竭力），expect（期待），fail（未履行），help（帮助），hesitate（犹豫），hope（希望），learn（学会），manage（设法），neglect（疏忽），offer（主动提出），plan（计划），prepare（准备），pretend（假装），proceed（接着做），promise（答应），prove（证明），refuse（拒绝），resolve（解决），seem（觉得好像），swear （发誓），tend（往往会），threaten（威胁），undertake（承诺），volunteer（自愿做），vow（发誓），want（想要），wish（希望）would like

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 happen to know the answer to your question. 我碰巧知道你那道问题的答案。

2在下列情况下，一般用不定式和动名词均可但有区别：

1）．hate,like,love，prefer，如：I'd like to have a cup of coffee. 动名词表示经常性，习惯性

不定式表示具体行为

2）当谓语动词begin,continue,star t等是进行式时多用不定式，

如：The students are starting to work on the difficult maths problem.

begin,continue,start与know,understand等状态动词连用时，如：I soon began to understand what was happening.

3）advise,allow,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/us 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 forget to 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.

5）.need, want, deserve，require+动名词表被动意义；+不定式被动态表示“要(修、清理等)”意思

6）有些动词后使用动名词和动词不定式作宾语的差别

1）forget to do 忘记要去做某事（未做）forget doing忘记做过某事（已做过或已发生）

2）stop to do 停止某件事，目的是去做另一件事stop doing 停止正在或经常做的事

3）remember to do 记住去做某事（未做）remember doing记得做过某事(已做)

4) regret to do对要做的事遗憾regret doing对做过的事遗憾、后悔

5）try to do努力、企图做某事try doing试验、试一试某种办法

6) mean to do打算，有意要…mean doing意味着

7）go on to do 继而（去做另外一件事情）go on doing 继续（原先没有做完的事情）

8）propose to do 打算（要做某事）proposing doing建议（做某事）

9) like /love/hate/ prefer +to do 表示具体行为；+doing sth 表示抽象、倾向概念

3 动词+疑问词+ 不定式

decide, know, consider forget, learn, remember, show, understand, see, wonder, 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 mind which to buy.有这么多的录音机，我都拿不定主意买哪一种。

3)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。如：

We think it quite important for us to learn a foreign language well.

He feels it his duty to help the poor.

I find it difficult to learn English well.

4作介词宾语时：在do nothing／anything／everything but(except) besides+to do(do)结构中。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：

Last night I did nothing but watch TV．昨天晚上，我除了看电视别的什么也没有干。

但是，如果谓语动词不是“do nothing，anything，everything”，那么but(except)所跟的不定式则仍须带。（前面有do,后面没to,前面没do,后面还原to）

There was nothing for them to do but remain silent．除了保持沉默以外，他们没有别有别的办法。The enemy soldiers had no choice but to give in.

On Sunday afternoon I had nothing to do but watch TV.

四．不定式作定语不定式作定语，刚在所修饰词的后面即后置定语, 时间上表将来

用不定式作定语的几种情况：

1.不定式表将来：

I borrowed some books to read during my holiday.

2. 不定式作定语，放在所修饰词的后面即后置定语。

There are a lot of students to do part time jobs this summer.

We have made a plan to finish the work

3.用来修饰被序数词、最高级或no, all, any 等限定的中心词。如：

He was the best man to do the job.

She was the first woman to win the gold medal in the Olympic Games.

Women and children were the first to get into the lifeboats.

4.用来修饰的词是抽象名词时，常见的有：ability, chance, idea, fact, excuse, promise, answer, reply, attempt, belief, way, reason, moment, time 等。如：

Do you have the ability to read and write English ?

I have the chance to go sight –seeing.

不定式修饰一些表示方向、原因、时间、机会、权利等抽象名词如：

ability能力，本领drive赶，驾驶movement运动，活动ambition抱负，野心effort努力，尝试need需要，需求campaign战役，运动failure失败，不及格opportunity机会

chance机会force力，压力，要点promise许诺，希望courage勇气intention意向，意图reason 理由，原因decision决定method方法，方式light光，光线，亮光determination决心，决定motive 动机，目的struggle奋斗，努力，tendency倾向，趋势wish希望，愿望，祝愿

5不定式修饰的名词或代词和不定式在逻辑上构成主谓关系时，不定式用主动形式。如：

Do you have a knife to cut the watermelon?

不定式修饰的名词或代词和不定式在逻辑上构成动宾关系，又和该句主语逻辑上构成主谓关系时，不定式用主动形式。如：

She has a sister to look after?

6 在there be 结构中当说话人考虑的是必须有人去完成某事时，不定式用主动形式；如果说话人强调的是事情本身必须被完成，则用被动形式。如：

There is a lot of work to do.

There is a lot of work to be done.

7作定语的不定式如果是不及物动词，或者不定式所修饰的名词或代词是不定式动作的地点、工具等，不定式后面须有相应的介词。如：

The Browns have a comfortable house to live in.

There is nothing to worry about.

Please give me a knife to cut with.

Here is some paper for you to write on.

但是，不定式所修饰的名词如果是time, place 或way时，不定式后面的介词习惯上省去。如：He had no money and no place to live (in). We found a way to solve this problem (in).

五．不定式做状语，只表示目的、结果，条件或原因等：

A）表目的：to ,in order to, so as to

He worked day and night to get the money.

She sold her hair to buy the watch chain.

注意不定式放句首时，逻辑主语与句子主语要一致：

wrong：To save money, every means has been tried.

right: To save money, he has tried every means.

wrong：To learn English well, a dictionary is needed.

right: To learn English well, he needs a dictionary

表示目的；它的否定式是so as not to do, In order not to

Tom kept quiet about the accident 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。

B）表结果：to,only to,so….as to

He arrived late to find the train gone. 常用only放在不定式前表示强调：

I visited him only to find him out.

C）表原因：

They were very sad to hear the news.

D）表程度：

It’s too dark for us to see anything.

He is old enough to go to school.

so kind as to ---劳驾

Would you be so kind as to tell me the time?

劳驾，现在几点了。

E)表条件：

To look at him,you will like him .

F) 作形容词的状语(主动表被动）

The question is simple for him to answer.

不定式作表语形容词的状语，和句子主语构成逻辑上动宾关系时，不定式用主动形式。如：This book is difficult to understand?

English is not easy to learn.

不定式的特殊句型

1) 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。

2)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. 我非常高兴能帮助你。

He was but too eager to get home. 他非常想回家。

3)cannot(never)….too 再。。。也不为过

You cannot be too careful in the street.

练习：

He hurried home only to find his money stolen. 他匆忙赶到家中，发现钱被盗了。（结果状语）To make himself heard, he raised his voice. 为了被听清楚，他提高了嗓门。（目的状语）

All of us are surprised to see his rapid progress. 看到他的进步，我们都很吃惊。(原因状语) He got up early in order to catch the first bus.

The bus stopped so as to pick up passengers.

He was too excited not to say few words.

He hurried to the station only to find that the train had left.

六．作补语

1) 动词+宾语+不定式(to do)

advise allow believe cause challenge compel（强迫, 使不得不）declare encourage forbid force find hire induce（引诱, 劝导）instruct（命令, 指示）invite like order permit persuade remind request require select send suppose tell train urge（催促，鼓励）

ask要求，邀请get请，得到prompt促使allow允许forbid禁止prefer喜欢，宁愿

announce宣布force强迫press迫使bride 收买inspire鼓舞request请求

assist协助hate憎恶pronounce断定，表示advise劝告exhort告诫，勉励pray请求

authorize授权，委托help帮助recommend劝告，推荐bear容忍implore恳求remind提醒

beg请求induce引诱report报告compel强迫invite吸引，邀请，summon传唤

command命令intend想要，企图show 显示drive驱赶mean意欲，打算train训练

cause引起instruct指示require要求deserve应受leave使，让tell告诉

direct指导like喜欢tempt劝诱entitle有资格order命令warn告诫enable使能够need需要urge激励，力说encourage鼓励oblige不得不want想要condemn指责，谴责lead引起，使得teach教entreat恳求permit允许wish希望

例句：

a.Father will not allow us 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。

下列动词后跟带to 的不定式作补语：

advise, allow, ask, beg, cause, encourage, expect, forbid, force, get, intend, invite, like, love, order, persuade, prefer, require, teach, tell, want, warn, wish, think, wait for, call on, depend on 等。如：

①An army spokesman stressed that all thd soldiers had been ordered to issue clear warning before firing any shots.

②The teacher asked us not to make so much noise.

③The flu is believed to be caused by viruses that like to reproduce in the cells inside the human nose and throat.

2) to + be 的不定式结构，作补语的动词。

Acknowledge 承认, 供认,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), understand

We consider 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。

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.

It is believed that…

人们认为这本书没什么意思。

有些动词需用as 短语做补语，如regard, believe, take, consider. Look on ,think of，count，treat 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。

3）分词、不定式作宾语补足语的区别

1．感官动词see, watch, observe, look at, hear, listen to, notice 等和使役动词have 后面的宾补有三种形式，即原形动词（不带to 的不定式）、现在分词和过去分词。现在分词表主动或正在进行，过去分词表被动或完成，动词原形表主动和完成。如：

I heard her sing an English song just now.

刚才我听见她唱了一首英文歌。

I heard her singing and English song when I passed by her room yesterday.

昨天经过她房间时，我听见她在唱英文歌。

I heard the English song sung many times.

我多次听到有人唱这首英文歌。

注意：不及物动词的过去分词作宾补表完成和状态。如：

I looked down at my neck and found my necklace gone. (状态)

I was surprised to find my hometown changed so much. (完成)

2．leave 后接三种形式作宾补时，其中的leave 保留了原来之义“留下”，但表达的确切之义应是“使……处于某种状态）。

leave sb. doing sth. 让某人一直做某事

（宾语和宾补之间是主谓关系，表示动作正在进行。）

leave sth. undone 留下某事未做

（宾语和宾补之间是动宾关系，表示被动和完成，一般以undone, unfinished, unsettled, untouched 为多）

leave sb. to do sth. 留下某人做某事leave sth. to be done 留下某事要做

（不定式表示将来的动作。）

如：It’s wrong of you to leave the machine running.

你让机器一直开着是不对的。（主动，正在进行）

The guests left most of the dishes untouched, because they didn’t taste delicious.

客人们没有动大部分菜，因为它们尝起来不可口。（被动，完成）

He left, leaving me to do all the rest work.

他走了，留下我一人去做剩余的工所有工作。（主动，将来）

We hurriedly ended our meeting, leaving many problems to be settled.

我们匆匆忙忙导结束了会议，留下了很多问题等待解决。（被动，将来）

3．have, get 后接三种形式作宾补时，其中heave, get 表示“使、让、叫”之意。

①have sth. done = get sth. done “使/让某事由别人去做”（叫/让某人做某事）。如

I’ll have /get my bike repaired tomorrow.

此外，have sth. done 还表示“使遭受……”之意。如

Tom had his leg broken while playing football.

Mr. Smith had his house broken into while he was away on holiday.

②have sb. / sth. doing 使/让某人/物持续地做某事（现在分词表示主动，正在进行）

get sb. / sth. doing 使某人/物开始行动起来

如：The peasants had the tractor working day and night at the harvest time.

农忙时，农民们让拖拉机夜以继日地干活。

The captain got the soldiers moving toward the front after a short rest.

休息了片刻之后，上尉让士兵们开始朝前线行进起来。

注意：“have sb. doing”若用于否定句中，其中have 有“容忍”之意。如：

I won’t have you speaking to your parents like that.

我不会让你那样子跟你的父母说话。

Don’t have the water running all the time.

不要让水流个不停。

③have sb. do sth. (get sb. to do sth. ) 使/让/叫某人去做某事

如：Mother had me go to the shop and buy some salt.

I can’t get him to stop smoking. He won’t listen to me.

find 的特殊用法：

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to 的动词不定式。find后也可带一个从句。此类动词还有get，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 ___ 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。

lie: 躺过去式lay,过去分词lain , 现在分词lying;

lie: 说谎过去式lied,过去分词lied , 现在分词lying;

lay:安放过去式laid,过去分词laid, 现在分词laying;

此外，介词有时也与这种复合宾语连用，如：

With a lot of work to do, he didn’t go to the cinema

三、不定式、现在分词作宾补小窍门

下列动词后在主动语态中用不带to 的不定式作补语，但在被动语态中要加上to：

它们是“吾看三室两厅一感觉”——5看（look at, see, watch, notice, observe）；3使（make, let, have）；2听（listen to, hear）；1感觉（feel）。以上动词还可用现在分词作宾语补足语（5+3+2+1-2+4）：即以上动词除let, make 外都可以用现在分词作宾语补足语，此外find, catch, keep, have 也可以用现在分词作宾语补足语。如：

At that time, I found him crying in the street.

He was caught stealing.

I’m sorry to have kept you waiting for such a long time.

The missing boys were last seen playing near the river.

不带to的不定式感官动词和使役动词

1）在表示生理感觉的动词后的不定式不带to。这类词有：

feel 觉得observe 注意到，看到overhear听到

watch注视listen to听perceive察觉，感知

notice注意see看见look at看hear听

On seeing the young child fell into the lake，Eric sprang to his feet，and went on the rescue.

2)另一类是某些使役动词，如make, let，have等。如：

Let him do it.让他做吧。

(注)：上述感觉动词与使役动词转换为被动结构时．其后的不定式一般需带to，如：

The boy was made to go to bed early.

学生操练实践

EXERCISES:

1.They would not allow him____ across the enemy line.

A. to risk going

B.risking to go

C. for risk to go

D.risk going

2.Though he had often made his little sister_ ___, today he was made____by his little sister.

A.cry,to cry

B.crying,crying

C.cry,cry

D.to cry,cry

3.As you've never been there before,I'll have someone_ ____you the way.

A.to show

B.show

C.showing

D.showed

4.---Good morning.Can I help you?

---I'd like to have this package_ __,madam.

A.be weighed

B.to be weighed

C.to weigh

D.weighed

5.It's very cold. Let's make a fire__ _____ ourselves.

A.warm

B.to warm

C.warming

D.warmed

6.I have a suggestion_ __at the meeting.

A.put forward

B.putting forward

C.to put forward

D.to be put forward

7.In Australia, he made a lot of friends__ ___a very practical knowledge of the English language.

A.get

B.to get

C.getting

D.got

8.I'm going to Shanghai next week.Have you anything__ ___ to your parents?

A.to buy

B.to be bought

C.to take

D.to be taken

9.The missing boy was last seen__ ___near the river.

A.playing

B.to be playing

C.play

D.to play

10.The boy who was caught_ ____in the examination will be punished by the teacher.

A.Cheat

B.cheating.

C.to cheat

D.cheated

11.The stranger you saw__ ___with a big travelling bag stayed in Room 104 yesterday.

A.to come in

https://www.360docs.net/doc/7f13980696.html,e in

C.has come in

D.who came in

12.When he was a boy, he used to go there and watched___ ___.

A.bicycles repaired

B.bicycles to be repaired

C.bicycles being repaired

D.to repair bicycles

13.Who did the teacher have__ ___an article for the wall newspaper just now?

A.written

B.writing

C.write

D.to write

答案：AABDB CBDAB BCC

注意这一结构的活用：

I saw the bike being repaired.

I saw the bike repaired.

We often heard the song being sung.

七．不定式的独立结构

To tell you the truth, to make things worse, to begin / start with

eg.I got lost in the street, to make things worse, I lost my wallet.

2.To tell you the truth,I really don’t know what he is talking about.

八．动词不定式的时态,语态

(1)时态

①一般式:动词不定式一般式表示的动作发生在谓语动词之后,有时表示同时发生.如:

I hope to become a university student this year.(to become发生在hope之后)

We often hear Dick play the piano in the next room.(play和hear同时发生)

②完成式:表示的动作发生在谓语动词所表示的动作之前.如:

I'm sorry to have kept you waiting.

We are too young to have seen the old society.

③进行式:表示的动作与谓语动词同时发生.如:

The teacher happened to be correcting our papers when I came in.

They seemed to be discussing something important.

(2)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)

一、不定式被动式的用法

不定式到底用主动形式还是被动形式，往往取决于句子的意思，即意思上为主动就用主动形式，意思上为被动就用被动形式：

Did it need to be done so soon? 这事需要这么快就做吗?

She can’t bear to be laughed at. 她受不了被人嘲笑。

There was business to be taken care of. 有生意要人管理。

It remains to be seen whether you are right. 你是否正确，以后见分晓。

There was a lot of rubbish to be got rid of. 有大量垃圾需要扔掉。

二、不定式完成被动式的用法

不定式的完成被动式表示发生在谓语动作之前的被动动作：

I’m pleased to have been given this opportunity. 给了我这次机会我很高兴。

It’s said to have been built in the Ming dynasty. 据说它是明朝修建的。

不定式完成式的三种用法

一、表示发生在谓语动作之前的动作

He seems to have caught a cold. 他似乎感冒了。

I hate to have quarreled with her. 我后悔和她吵架了。

I believe it to have been a mistake. 我相信这是一个错误。

You appear to have travelled quite a lot. 你似乎作过多次旅行。

I’m sorry to have given you so much trouble. 对不起给了你这么多麻烦。

It’s said to have been built in the Ming dynasty. 据说它是明朝修建的。

二、表示在某个给定的时间之前已完成的动作

I hope to have finished the work by now. 我希望现在以前已完成这项工作。

三、表示过去未曾实现的想法和愿望

I should like to have come earlier. 我本想早点来的。

We were to have been married last year. 我们本来打算去年结婚的。