动词不定式指什么?有什么用?

2024-11-25 13:29:29
推荐回答(5个)
回答1:

英语语法--动词不定式

动词不定式

7.1 不定式作宾语

1) 动词+ 不定式

afford aim appear agree arrange ask be decide bother care choose come dare demand desire determine expect elect endeavor hope fail happen help hesitate learn long mean manage offer ought plan prepare pretend promise refuse seem tend wait wish undertake

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)动词+不定式 ; 动词+宾语+不定式

ask, beg, choose, expect , hate, help intend like, love, need prefer, prepare, promise, want, wish…

I like to keep everything tidy. 我喜欢每件东西都保持整洁。

I like you to keep everything 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+ to

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。

注意:疑问词带不定式在句中作成分时,谓语动词用单数。

The question is how to put it into practice.

问题是怎样把它付诸实施。

7.1 不定式作宾语

1) 动词+ 不定式

afford aim appear agree arrange ask be decide bother care choose come dare demand desire determine expect elect endeavor hope fail happen help hesitate learn long mean manage offer ought plan prepare pretend promise refuse seem tend wait wish undertake

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)动词+不定式 ; 动词+宾语+不定式

ask, beg, choose, expect , hate, help intend like, love, need prefer, prepare, promise, want, wish…

I like to keep everything tidy. 我喜欢每件东西都保持整洁。

I like you to keep everything 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+ to

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。

注意:疑问词带不定式在句中作成分时,谓语动词用单数。

The question is how to put it into practice.

问题是怎样把它付诸实施。

7.2 不定式作补语

1) 动词+宾语+不定式(to do)

advise allow appoint believe cause challenge command compel consider declare drive enable encourage find forbid force guess hire imagine impel induce inform instruct invite judge know like order permit persuade remind report request require select send state suppose tell think train trust understand urge warn

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。

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。

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), 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。

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 do sth. 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。

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, undrstand

We didn’t expect there to be so many people there.我们没料到会有那么多人在哪里。

注意 : 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。

7.3 不定式主语

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, better;

the first, the next, the last, the best, too much, too little, not enough

It’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, thoughtful, thoughtless, brave, considerate(考虑周到的), 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 is… to…的句型

(对)To see is to believe. 百闻不如一见。

(错)It is to believe to see.

7.4 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 languages. 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, right。

It’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。)

7.5 不定式作表语

不定式可放在be动词后面,形成表语。例如:

My work is to clean the room every day.

His dream is to be a doctor.

7.6 不定式作定语

不定式做定语通常要放在被修饰的词后。例如:

I have a lot of work to do.

So he made some candles to give light.

7.7 不定式作状语

1)目的状语

To… only to (仅仅为了), in order to, so as to, so(such)… as to… (如此……以便……)

He ran so fast 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 ___.

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"形容词+动词不定式"结构的末尾。

7.8 用作介词的to

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 forward to 盼望, pay attention to 注意

7.9 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 him 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 sth:

7) 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 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.

A. learn B. to learn C. learned D. learning

答案:B. make后接不带to 的动词不定式,当其用于被动时,to 不可省略。

7.10 动词不定式的否定式

Tell him not to shut the window…

She pretended not to see me when I passed by. 我走过的时候,她假装没看见。

典型例题

1)Tell him ___ the window.

A. to shut not B. not to shut C. to not shut

D. 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 see

D. 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. Smith warned her daughter ___ after drinking.

A. never to drive B. to never driver

C. 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 it

D. do not to

答案:A。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 eat

D. not eating

答案:C。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。

7.11 不定式的特殊句型too…to…

1)too…to 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 afraid 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. 我非常高兴能帮助你。

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

7.12 不定式的特殊句型so as to

1) 表示目的;它的否定式是so as not to do。

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。

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。

7.13 不定式的特殊句型Why not

"Why not +动词原形"表达向某人提出建议,翻译为:"为什么不……?" "干吗不……?"

例如:

Why not take a holiday?

干吗不去度假?

7.14 不定式的时态和语态

时态\语态 主动 被动

一般式 to do to be done

进行式 to be doing

完成式 to have done to have been done

完成进行式 to have been doing

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 you 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.

7.15 动名词与不定式

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,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) 动名词与不定式语义不同的有11 组:

1 stop to do stop doing

2 forget to do forget doing

3 remember to do remember doing

4 regret to do regret doing

5 cease to do cease doing

6 try to do try doing

7 go on to do go on doing

8 afraid to do afraid doing

9 interested to do interested doing

10 mean to do mean doing

11 begin/ start to do begin/ start doing

回答2:

动词不定式是一种非限定性动词,由to+动词原形构成,但它还是属于动词,所以它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。动词不定式的特殊情况也要掌握。

第一节 动词不定式的构成与形式

一、动词不定式的概念:动词不定式指由to 加上动词原形(而且只能是动词原形)所构成的一种非限定性动词,但在有些情况下to可以省略。动词不定式在语法功能上可作主语1) 、宾语2)、表语3)、定语4) 和状语5)

1) education is the principal way of gaining status in a culture that generally stresses achievement,skillfulness,and upward mobility.

〔A〕 To acquire〔B〕 Acquire〔C〕 Acquires〔D〕 Have acquired

2) We are planning for the entrance examination for postgraduate.

〔A〕 registering〔B〕 register〔C〕 to register 〔D〕 registered

3) The most urgent problem now we are facing is to learn the needed materials for the matriculation of postgraduate.

〔A〕 make our every effort〔B〕 to make our every effort

〔C〕 to our every effort〔D〕 made our efforts

4) -Where should I send my application?

-The Personnel Office is the place it to.

〔A〕 sends〔B〕 be sended〔C〕 to be sended 〔D〕 to send

5) from others, one should take his promise.

〔A〕 To get confidence 〔B〕 To getting confidence

〔C〕 To get confidences〔D〕 Getting to the confidence

说明:以上五句中的斜体是其动词不定式的附属部分。

二、动词不定式的构成与形式: 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〔2〕和4〕中的斜体部分〕和状语〔5〕中的斜体部分〕。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 .考研题中,语法中所考动词不定式部分包括检测考生是否掌握动词不定式与其逻辑主语之间的一致,其中主要包括它们之间 主动和被动 的关系以及 它们在时间上的一致 ,同时动词不定式还有其否定形式。所有这些涉及到动词不定式的各种形式。现以动词make为例,其形式如下:

主动形式 被动形式

一般式 (not) 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

6) Some 〔A〕 types of naphtha(石油脑) are employed to dissolving 〔B〕 rubber 〔C〕 and to thin paints and 〔D〕 varnish.

7) The Statue of Liberty was originally 〔A〕 proposed 〔B〕 in 1865 to commemoration 〔C〕 the alliance 〔D〕 of France with the American colonies during the American Revolution.

8) The purpose 〔A〕 of inductive logic 〔B〕 is to inferring 〔C〕 general laws from particular occurrences 〔D〕 .

三、例题解析

1) A为正确答案。2) C为正确答案。3) B为正确答案。4) D为正确答案。5) A为正确答案。

6) B错。改用动词原形“dissolve”,不定式符号“to”后只能出现动词原形。

7) C错。改为“commemorate”。8) C错。改为“to infer”,注意句子的主语为“purpose”(目的)。

回答3:

动词不定式用法解读动词不定式是一种活跃的非谓语动词。它在句中起的是名词。形容词或副词的作用,可在句子中作主语。宾语。定语。状语和宾语补足语。动词不定式的形式是#to +动词原形#,但to有时要省去。动词不定式在具体运用时,用不用to,取决于谓语动词的用法:
一。带to的不定式结构

1.我们学过的能直接跟带to的不定式结构的动词主要有:want, ask, tell, hope, learn, try, decide, forget, remember, like ,love, stop, go, come等。

2.动词不定式的否定形式是在不定式前直接加not,即not to do sth.。例如:

Jim told me not to wake up Kate.吉姆告诉我别叫醒凯特。

二。不带to的不定式结构

以下几种情况使用不带to的动词不定式:

1.在固定词组had better之后。注意:had better的否定形式是had better not do sth.。例如:

You had better go home now.你最好现在回家。

It]s cold outside. You]d better not go out.外面很冷,你最好不要出去。

2.在let,make,see, feel, watch,hear等感官或使役动词后,要跟不带to的动词不定式作宾语补足语。例如:

I made them give me the money back.我迫使他们把钱还给我。

I didn]t see you come in.我没看见你进来。

3.在引导疑问句的why not之后。

#Why not+不带to的不定式#是Why don]t you do…的省略,可以用来提出建议或劝告。例如:

Why not go with us。为什么不和我们一起去呢。

Why not take a holiday。=Why don]t you take a holiday。为什么不休个假呢。

三。动词不定式作主语

不定式结构作主语时,现代英语倾向于采用it作形式主语,而把不定式结构后置的形式。参见本期本面《#小鬼it#它当家》中it作形式主语的用法。

四。动词不定式作定语

不定式作定语,要放在它所修饰的名词或代词的后面。例如:

I have nothing to say on this question.对这个问题我无可奉告。

五。动词不定式作宾语

有的及物动词要求跟复合宾语(即宾语+宾语补足语)。如果其中的宾语是不定式短语,则必须将形式宾语it放在宾语的位置上,而将不定式短语(真正的宾语)放在宾语补足语之前。例如:

I find it useful to learn English well.我发现学好英语很有用。

We thought it wrong not to tell her.我们认为不告诉她是错误的。

六。动词不定式作宾语补足语

动词不定式作宾语补足语是动词不定式用法的一个重点,学习时要注意以下三种情况:

1.作动词ask, like, tell等的宾语补足语时,动词不定式符号to不可以省略。例如:

He asked me to talk about English study.他请我谈谈英语学习。

2.作使役动词let, have, make以及感官动词feel, hear, see, watch等的宾语补足语时,动词不定式符号to要省略。例如:

The teacher made him say the word like this.老师让他像这样说这个单词。

3.作动词help的宾语补足语时,动词不定式符号to可以带,也可以不带。例如:

Could you help me (to) carry the heavy box。你能帮我搬这个重箱子吗。

七。动词不定式作状语

动词不定式及其短语具有副词的特性,可在句中用作状语。

1.放在句首也可以放在句尾表示目的等。例如: He stopped to have a rest.他停下来休息。

2.跟在作表语的形容词或过去分词的后面。例如:

I]m sorry to hear that.听到这事我感到很难过。

3.用在too... to...结构中。例如:

He is too young to understand all that.他太年轻了,不能理解这件事。

回答4:

.1 不定式作宾语

1) 动词+ 不定式
afford aim appear agree arrange ask be decide bother care choose come dare demand desire determine expect elect endeavor hope fail happen help hesitate learn long mean manage offer ought plan prepare pretend promise refuse seem tend wait wish undertake
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)动词+不定式 ; 动词+宾语+不定式
ask, beg, choose, expect , hate, help intend like, love, need prefer, prepare, promise, want, wish…
I like to keep everything tidy. 我喜欢每件东西都保持整洁。
I like you to keep everything 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+ to
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。

注意:疑问词带不定式在句中作成分时,谓语动词用单数。
The question is how to put it into practice.
问题是怎样把它付诸实施。
英语语法--动词不定式

动词不定式

7.1 不定式作宾语

1) 动词+ 不定式

afford aim appear agree arrange ask be decide bother care choose come dare demand desire determine expect elect endeavor hope fail happen help hesitate learn long mean manage offer ought plan prepare pretend promise refuse seem tend wait wish undertake

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)动词+不定式 ; 动词+宾语+不定式

ask, beg, choose, expect , hate, help intend like, love, need prefer, prepare, promise, want, wish…

I like to keep everything tidy. 我喜欢每件东西都保持整洁。

I like you to keep everything 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+ to

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。

注意:疑问词带不定式在句中作成分时,谓语动词用单数。

The question is how to put it into practice.

问题是怎样把它付诸实施。

7.1 不定式作宾语

1) 动词+ 不定式

afford aim appear agree arrange ask be decide bother care choose come dare demand desire determine expect elect endeavor hope fail happen help hesitate learn long mean manage offer ought plan prepare pretend promise refuse seem tend wait wish undertake

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)动词+不定式 ; 动词+宾语+不定式

ask, beg, choose, expect , hate, help intend like, love, need prefer, prepare, promise, want, wish…

I like to keep everything tidy. 我喜欢每件东西都保持整洁。

I like you to keep everything 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+ to

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。

注意:疑问词带不定式在句中作成分时,谓语动词用单数。

The question is how to put it into practice.

问题是怎样把它付诸实施。

7.2 不定式作补语

1) 动词+宾语+不定式(to do)

advise allow appoint believe cause challenge command compel consider declare drive enable encourage find forbid force guess hire imagine impel induce inform instruct invite judge know like order permit persuade remind report request require select send state suppose tell think train trust understand urge warn

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。

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。

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), 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。

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 do sth. 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。

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, undrstand

We didn’t expect there to be so many people there.我们没料到会有那么多人在哪里。

注意 : 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。

7.3 不定式主语

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, better;

the first, the next, the last, the best, too much, too little, not enough

It’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, thoughtful, thoughtless, brave, considerate(考虑周到的), 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 is… to…的句型

(对)To see is to believe. 百闻不如一见。

(错)It is to believe to see.

7.4 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 languages. 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, right。

It’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。)

7.5 不定式作表语

不定式可放在be动词后面,形成表语。例如:

My work is to clean the room every day.

His dream is to be a doctor.

7.6 不定式作定语

不定式做定语通常要放在被修饰的词后。例如:

I have a lot of work to do.

So he made some candles to give light.

7.7 不定式作状语

1)目的状语

To… only to (仅仅为了), in order to, so as to, so(such)… as to… (如此……以便……)

He ran so fast 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 ___.

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"形容词+动词不定式"结构的末尾。

7.8 用作介词的to

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 forward to 盼望, pay attention to 注意

7.9 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 him 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 sth:

7) 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 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.

A. learn B. to learn C. learned D. learning

答案:B. make后接不带to 的动词不定式,当其用于被动时,to 不可省略。

7.10 动词不定式的否定式

Tell him not to shut the window…

She pretended not to see me when I passed by. 我走过的时候,她假装没看见。

典型例题

1)Tell him ___ the window.

A. to shut not B. not to shut C. to not shut

D. 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 see

D. 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. Smith warned her daughter ___ after drinking.

A. never to drive B. to never driver

C. 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 it

D. do not to

答案:A。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 eat

D. not eating

答案:C。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。

7.11 不定式的特殊句型too…to…

1)too…to 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 afraid 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. 我非常高兴能帮助你。

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

7.12 不定式的特殊句型so as to

1) 表示目的;它的否定式是so as not to do。

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。

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。

7.13 不定式的特殊句型Why not

"Why not +动词原形"表达向某人提出建议,翻译为:"为什么不……?" "干吗不……?"

例如:

Why not take a holiday?

干吗不去度假?

7.14 不定式的时态和语态

时态\语态 主动 被动

一般式 to do to be done

进行式 to be doing

完成式 to have done to have been done

完成进行式 to have been doing

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 you 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.

7.15 动名词与不定式

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,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) 动名词与不定式语义不同的有11 组:

1 stop to do stop doing

2 forget to do forget doing

3 remember to do remember doing

4 regret to do regret doing

5 cease to do cease doing

6 try to do try doing

7 go on to do go on doing

8 afraid to do afraid doing

9 interested to do interested doing

10 mean to do mean doing

11 begin/ start to do begin/ start doing
编辑词条

动词不定式是一种非限定性动词,由to+动词原形构成,但它还是属于动词,所以它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。动词不定式的特殊情况也要掌握。

第一节 动词不定式的构成与形式

一、动词不定式的概念:动词不定式指由to 加上动词原形(而且只能是动词原形)所构成的一种非限定性动词,但在有些情况下to可以省略。动词不定式在语法功能上可作主语1) 、宾语2)、表语3)、定语4) 和状语5)

1) education is the principal way of gaining status in a culture that generally stresses achievement,skillfulness,and upward mobility.

〔A〕 To acquire〔B〕 Acquire〔C〕 Acquires〔D〕 Have acquired

2) We are planning for the entrance examination for postgraduate.

〔A〕 registering〔B〕 register〔C〕 to register 〔D〕 registered

3) The most urgent problem now we are facing is to learn the needed materials for the matriculation of postgraduate.

〔A〕 make our every effort〔B〕 to make our every effort

〔C〕 to our every effort〔D〕 made our efforts

4) -Where should I send my application?

-The Personnel Office is the place it to.

〔A〕 sends〔B〕 be sended〔C〕 to be sended 〔D〕 to send

5) from others, one should take his promise.

〔A〕 To get confidence 〔B〕 To getting confidence

〔C〕 To get confidences〔D〕 Getting to the confidence

说明:以上五句中的斜体是其动词不定式的附属部分。

二、动词不定式的构成与形式: 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〔2〕和4〕中的斜体部分〕和状语〔5〕中的斜体部分〕。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 .考研题中,语法中所考动词不定式部分包括检测考生是否掌握动词不定式与其逻辑主语之间的一致,其中主要包括它们之间 主动和被动 的关系以及 它们在时间上的一致 ,同时动词不定式还有其否定形式。所有这些涉及到动词不定式的各种形式。现以动词make为例,其形式如下:

主动形式 被动形式

一般式 (not) 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

6) Some 〔A〕 types of naphtha(石油脑) are employed to dissolving 〔B〕 rubber 〔C〕 and to thin paints and 〔D〕 varnish.

7) The Statue of Liberty was originally 〔A〕 proposed 〔B〕 in 1865 to commemoration 〔C〕 the alliance 〔D〕 of France with the American colonies during the American Revolution.

8) The purpose 〔A〕 of inductive logic 〔B〕 is to inferring 〔C〕 general laws from particular occurrences 〔D〕 .

三、例题解析

1) A为正确答案。2) C为正确答案。3) B为正确答案。4) D为正确答案。5) A为正确答案。

6) B错。改用动词原形“dissolve”,不定式符号“to”后只能出现动词原形。

7) C错。改为“commemorate”。8) C错。改为“to infer”,注意句子的主语为“purpose”(目的)。

1. 不定式前置
1) Derive 〔A〕 mineral resources from 〔B〕 sedimentary rock 〔C〕 is a 〔D〕 major modern industrial activity.
2) in the matriculation for postgraduate in a short time is realy a hard nut.
〔A〕 To make high scores
〔B〕 To make low goal
〔C〕 To the high scores
〔D〕 Make the low goals

2. 上述形式一般情况不多见,作为考试的规范英语,如果不定式较长,显得头重脚轻,则可由代词“it”作形式主语(形式主语“it”不能由“that”或“this”等其他代词代替),而将不定式放到后面
It is really a hard nut to get high scores in the matriculation for postgraduate in a short time.
3) John admitted that it's always difficult .
〔A〕 for him being on time
〔B〕 being on time for him
〔C〕 for him to be on time
〔D〕 on time for him
4) It is difficult for me 〔A〕 to be concentrating 〔B〕 while someone 〔C〕 is using 〔D〕 a vacuum cleaner.

3. 不定式后置的情况不仅限于动词是系动词,也适用于其他动词
It took us a great deal of efforts to finish that task.
It made him extremely happy to get contact with his family in Taiwan since they separated more than 40 years ago.

4. 不定式结构所表示的动作是谁做的,即不定式的逻辑主语,通常可以在特定的上下文中能看出,也可以通过带“for +名词短语”辨出
It is quite important for us to read good books during the period of general review(总复习).
It is not difficult for those who study maths well to pass the exam.

5. 在某些形容词(如careless,clever,considerate, foolish, good, impolite, kind, naughty, nice, silly, stupid等)作表语时,不定式后可以加of来引导出其逻辑主语
It is very kind of you to help me./It is stupid of him to do such a silly thing.
间或也可用for + there to be 表示(而且there后面的不定式只能是to be)。
It's a great pity for there to be much trouble in the company.

二、 不定式作宾语
不定式作宾语有两种:一种是及物动词后直接跟带to的不定式;另一种是“动词+疑问词+带to的不定式”
1. 动词+带to的不定式结构
只能跟动词不

回答5:

to 加动词原形即为不定式基本形式,它属于非谓语,可做主语,宾语,定语,状语等