高中英语语法讲解不定式
（The Infinitive）
定义：动词不定式是非谓语动词的一种，它没有人称和数的变化，在句子中不能独立作谓语，但它仍保持动词的特点，既可以有自己的宾语和状语。 E.g. He want his students to read the book aloud.
A．
1不定式的构成（以动词do为例）
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 无
完成进行式to have been doing 无
2不定式的意义
不定式的一般式(to do )
一般式表示的动作或状态，发生在谓语动词表示的动作或状态的同时或之后
My wish is to become a doctor
He seemed to be tired.
She stopped to have a rest.
不定式的被动式 (to be done)
当不定式的逻辑主语是这个不定式所表示的动作的承受者时,不定式一般要用被动式.
The building to be finished next month is for our teachers.
I am going to Beijing, I have something to take to my parents, do you have something to be taken to your parents?
如果谓语表示的动作(情况)发生时, 不定式表示动作正在进行,这时候不定式就要用进行式.（to be doing）
They are said to be building another bridge across the street.
They seemed to be talking about something important.
When I went to his home, he happened to be traveling around the world.
I’m glad to be working with you.
如果不定式所表示的动作或状态发生在谓语动词所表示动作或状态之前，就用完成式 (to have done) ；若是在此基础上的被动含义，就用完成被动式( to have been done).
He is said to have written a novel about the Long March.
He thought it a pity not to have invited us.
The assistant seemed to have been fired.
He is said to have been taught French when he was a child.
Einstein is said to have built up his theory when he was in his twenties.
如果不定式的动作是在谓语所表示的时间之前一直在进行的动作，就要用完成进行式.
They are said to have been collecting folk song in Xinjiang.
We’re happy to have been working with the experts all the month.
B. 用法：
动词不定式具有名词、形容词和副词的特征。因此在句中可以做主语、表语、宾语、宾语补足语、定语和状语。
一、不定式做主语：
1、不定式做主语一般表示具体的某次动作。===动名词doing 表示习惯的，经常的动作。
e.g: To finish the building in a month is difficult.
To do such things is foolish.
To see is to believe. (对等)
注: 1). 不定式作主语时,谓语用单数
2). 当主语较长，谓语较短时，常用it做形式主语，而将不定式放到谓语的后面。
it做形式主语，不定式放在谓语动词之后常用于下列结构中：
(1)It is/was +adj.+of sb. to do…
(2) It is +adj.+for sb.+to do…
It is easy / difficult / hard / foolish / unwise / right / wrong / unnecessary
(3) it is +a +名词+ to do...
It is a pity / a pleasure / a pleasant thing / one’s duty / an honor / a shame / a crime / no easy job… to do
It takes (sb.) some time / courage / patience …to do…
It requires courage / patience / hard work… to do…
*注意: probable 和 possible 均可作表语，但possible可以用不定式作真实主语，而probable不能用不定式作真实主语。
It is probable for him to come to the meeting.(错）
It is possible for him to come to the meeting.
It is possible / probable that he will come to the meeting.
二、不定式做表语
主语是以aim duty hope idea intention plan job suggestion wish purpose task 等为中心词的名词词组或以 what 引导的名词性从句表示，后面的不定式说明其内容, 不定式作表语常表示将来或现在的动作或状态。
eg My idea is to climb the mountain from the north.
Your mistake was not to write that letter.
What I would suggest is to start work at once.
三动词不定式作宾语
以不定式结构为宾语的动词有：
ask, agree, care, choose, demand, decide, expect, fail, help, hope, learn, manage, offer, plan, prepare, pretend, promise, refuse, want, wish等只能用动词不定式作宾语
口诀（接不定式作宾语的动词）
想要学习早打算（ want learn plan）
快准备有希望（ prepare hope wish expect）
同意否供选择（agree offer choose）
决定了已答应（decide be determined promise）
尽力去着手做（manage undertake）
别拒绝别假装（refuse pretend）
失败不是属于你（fail）
e.g.Tom refused to lend me his pen.
We hope to get there before dark.
The girl decided to do it herself.
*注意:某些及物动词可用-ing也可用动词不定式作宾语但意义不同的有
stop go on remember forget
regret try mean can’t help
be used to
四．动词不定式做定语
1．. 不定式作定语需要后置。
2. 作定语的不定式与被修饰的名词或代词存在着两种主要的逻辑关系，即被修饰的名词和代词是不定式
的逻辑主语（逻辑上的主谓关系）或逻辑宾语（逻辑上的动宾关系）
1）不定式前的名词是它的逻辑主语。
He is the doctor to do the operation.
2) 不定式和它所修饰的名词是逻辑上的动宾关系。
I have a lot of things to do.
3）不定式前的名词是它修饰的对象。
This is the right time to start.
注意．如果不定式所修饰的词是way 或 place, 介词可省略。
He has no way to go (by). This is the best place to work (at)
五．宾语补足语
He want you to be his assistant. I saw her cross the street.
[注1] 如果谓语动词为感官动词或使役动词，则作宾补的不定式不可带to，这些动词有see, hear,
feel, watch, notice; have, make, let等。
I felt my blood run cold. What made you think like that?
但如果句子是被动语态，则to不可省略。
He was made to clean the windows as a punishment.
Someone was heard to come up the stairs.
[注2] 1.谓语动词help后可接带to或不带to的不定式作宾补。用不带to的不定式表示帮助者直接参与动作；用带to的不定式表示主语没有直接参与动作。
They helped me carry the boxes.
This kind of soap will help you to wash the clothes more easily.
2.在美式英语或非正式文体中，help后用作宾补的不定式均不带to。
3.help后可以直接用带to或不带to的不定式作宾语。
They helped (to) carry the furniture upstairs.
[注3]look at及listen to后用作宾补的不定式不带to（这主要是美式英语）。
We have been listening to the radio tell a long story.
六．表语补足语当不定式与主语存在逻辑上动宾关系的时候，用主动表被动。
That is hard to say. The chair is comfortable to sit in.
七．不定式做状语
不定式做状语修饰动词、形容词、副词等，表示目的、原因、结果、条件等。
1、表目的
e.g. To learn a foreign language well, you must try your best (主语一致) He came here to attend an important meeting.
He came here in order to see Charlie.
I turned the radio down so as not to disturb him
注：表示目的的不定式可以置于句首，这也是区别于其他功能的标志之一。
* 但是，置于句首表示目的的不定式可以是to, in order to ，但却不可以是so as to. ”,” To draw
maps properly, you need a special pen.
In order to draw maps properly, you need a special pen.
To get the best results, use clean water.
To be elected monitor of our class, he gave money to us.
* 放在句末时， to do 表示目的，不可有“，”若有用doing 表示伴随的目的
e.g. He bowed to us to thank us for helping him find the way.
He worked day and night, hoping to finish the work beforehand.
注：1. 不定式结构表示目的时，通常句子的主语就是它的逻辑主语 (主语一致)
e.g.He bought a bicycle to go to town more quickly.
He went home to see his mother.
例外 e g He opened the door for the children to come in.
They sent a man to mend the window.
2、表结果
不定式结构表示结果更常见于下列句型
① so …as to …
Would you be so kind as to lend me your bicycle / tell me the time?
② such (…) as to …
I’m not such a fool as to believe that.
③ adj./adv. + enough to …
The boy is old enough to go to school.
④ too … to …
His eyesight is too poor to read such small letters.
（5）only to find , only to be told 出乎意料之外的结果
3．原因不定式可以用于动词、形容词或-ed分词后表示原因。
He was too excited to get high marks.
八．同位语
Is this your purpose, to avoid being punished?
九．独立成分
To tell you the truth, I don’t like you. They arrived here at 11:55 a.m., to be exact.
类似的有：to be frank坦率地说，to hear him talk听他说话的口气，to cut a long story short 长话短说，等等。
C
不定式的各种结构
1．宾格词 + 不定式
1）普通结构此结构中的宾格词为名词或代词的宾格，宾格词是谓语动词的宾语，同时又是不定式的逻辑主语，不定式和宾格词一起构成复合宾语。
I want Henry to come. She expects this to be true. I heard them sing yesterday.
2) “there to be + 宾格词”结构
此结构的宾格词仍是不定式的逻辑主语，只是它位于不定式to be 的后面。
I don’t want there to be any misunderstanding.
3) 各种形式的不定式都可以用于此种结构中。
The judge wanted the man to be punished.
He expected each of his students to be working hard for the coming exam.
2．主格词 + 不定式
当上一种结构变为被动语态时，就出现了此种结构，此结构中，不定式都要带to，主格词是不定式的逻辑主语，不定式在句中作主语补足语。
They are allowed to go. ← We allowed them to go.
He was seen to enter the store. ← I saw him enter the store.
3．for + 宾格词 + 不定式
此结构中，宾格词是不定式的逻辑主语，这种结构在句中可作：
1）主语 It is difficult for us to learn a second foreign language.
2）宾语 I consider it necessary for her to learn French.
3）表语 The best thing is for us to make our own decision.
4）定语 There is a lot of work for us to do.
5）状语 He opened the door for the car to enter.
The book is too easy for them to read.
4．with/without + 宾格词 + 不定式
此结构在句中常作原因状语，宾格词是不定式的逻辑宾语。
With so much work to do, I shall not be able to watch the match with you.
Without anything to eat, he died of hunger.
5．疑问词 + 不定式此结构相当于名词词组，在句中可作：
1）主语 When to visit that farm has not been decided yet.
2）宾语 We must know how to operate this machine.
3）表语 The problem now is how to collect enough money.
4）同位语 The problem what to do next is unknown.
注意 intend, plan, hope, expect, mean, promise, want, think, wish, were (was), would like, should like + 不定式完成式，可表过去没有实现的愿望，期待和计划。
He intended to have come. = He intended to come, but he didn’t.
She wished to have bought a car. = She wished to buy a car, but she didn’t.
I meant to have called on you, but I was too busy.
She hoped to have passed the exam. (but she didn’t)
I would like to have gone abroad. (but I didn’t)
D
不定式的否定式
通常是在不定式前加not，表示较强的否定意义时可用never。
I told him not to touch the equipment. You must promise never to do that again.
E特殊动词不定式的“省略与保留”
一、不定式符号的省略与保留
1. 在had better, would rather, would rather...than, would sooner...than,
cannot but, why (not)等结构后面的不定式符号to通常被省略。如:
You’d better tell her the truth. 你最好告诉她真相。
2. 动词不定式短语作介词but, except, besides的宾语,且介词之前有行为动词do或它的其它形式时,不定式符号to通常被省略。如:
What do you like to do besides swim?
除了游泳,你还喜欢干什么?
My mother could do nothing but wait for the doctor to arrive.
妈妈只好等着医生的到来。
Now he had given himself no choice but to tell her. (本句中不定式符号to不可省略)
当时他毫无选择的余地,只好告诉她了。
3.两个或多个不定式短语表示并列关系时,后面不定式短语的不定式符号to通常被省略;如果表示对比关系,则不定式中的不定式符号to通常要保留。如:
They didn’t tell me whether to go on or to stop.(对比关系)
他们没有告诉我是继续下去还是停止。
She told the child to stay there and wait till she came back.(并列关系)
她让孩子待在那里等她回来。
4.在某些感官动词或使役动词(如 hear, listen to, notice, observe, see, watch,
make等)之后充当宾语补足语的不定式中,不定式符号to总是被省略,但在被动语态的句子中,不定式符号to通常要保留。如:
They made that man work all the morning.
他们让那个人干了一个早晨。
That man was made to work all the morning.
那个人被要求干了一个早晨。
5. 不定式短语作表语,不定式符号to常常要保留,但当what引导的名词性从句作主语,或all, everything等后接定语从句作主语,从句谓语部分含有动词do或do的其他形式时,作表语的不定式可以保留也可省略不定式符号to。如:
The greatest happiness is to work for the happiness of all.
最大的幸福就是为大家的幸福而工作。
The only thing I can do now is (to)go on by myself.
我现在唯一能做的就是靠自己继续进行下去。
二、不定式符号后面动词的省略与保留
1. 为了避免重复,在hope, wish, want, like, love, decide, plan, mean, prefer,
want, have to, be able to, be going to, used to, ought to等动词及习语后面出现与上文相同的不定式时,常保留不定式符号to,而把其它部分省略。如:
Ms King lied to us because she had to.
金女士跟我们撒了谎,因为她不得不这样做。
－I heard that you would go to Dalian for your holiday.
我听说你要去大连度假。
－I planned to, but I have some important business to deal with.
我原计划去的,但有重要的事情要处理。
2.当不定式在ask, advise, persuade, wish, allow, permit, tell, expect, force, invite, beg等动词后面充当宾语补足语时,为了避免重复,常保留不定式符号,而把后面的动词省略。如: She wants to come but her parents won’t allow her to.
她想来,但她的父母不允许。
If he doesn’t want to go there, don’t force him to.
如果他不想去那里,别强迫他。
He didn’t come, though we had invited him to.
虽然我们邀请了他,但他没来。
－Did your husband give up smoking?
你丈夫戒烟了吗?
－No. He was advised to, but he wouldn’t listen.
没有。有人劝过他,但他就是不听。
3. 在特定的上下文中,为了避免重复,如果不定式为一般式to be...或完成式to have done时,则不定式符号to和be或have常一并保留,be或have之后的部分通常要省略。如:
－Aren’t you the headmaster?
你难道不是校长吗?
－No, and I don’t want to be.
我不是,而且我也不想当。
－Hasn’t he finished writing the report?
难道他还没写完报告吗?
－No, but he ought to have.
是的,但他本来应该写完。
F
常见的含有动词不定式的句式主要有以下几种：
一.
It takes sb. some time （money）to do sth.
某人花费多少时间（金钱）做某事。例如：
1. It often takes me half an hour to watch TV every evening.
每天晚上我常常用半小时看电视。
2. It took me ten yuan to buy the book last week.
上周我花了10元买那本书。
3. How long will it take them to finish the work?
完成那项工作需要花费他们多少时间？
在使用该句式要注意的是：sb. 如果代词表示用宾格；take随时态改变；句中的时间用段时间，对此提问用how long。
例：It takes us more than two hours to do our homework every day.
It took us more than two hours to do our homework yesterday.
It will take us more than two hours to do our homework tomorrow.
How long did it take you to do your homework yesterday?
二. It’s time to do sth. 该做某事了，同义句为：
It’s time for sth. / doing sth. 例：
It’s time to go to school. 该上学了。
（It’s time for school.）
It’s time to get up. 该起床了。
（It’s time for getting up.）
此句可以扩展为：It’s time for sb. to do sth.
是某人做某事的时间了。
for sb. to do sth. 是动词不定式的复合结构。例：
It’s time for me to work.
到我工作的时间了。
It’s time for you to go to school.
到你们上学的时间了。
三. 主语＋be（not）+adj.+enough to do sth.
（某人、某物）足够（不能）做某事。例：
The boy is old enough to go to school.
这个孩子到了上学年龄。
I’m tall enough to reach the top of the tree.
我够高能够到树顶。
*1. 此句是肯定句时，可以用主＋be＋so＋adj.＋that的句型（即so…,that…表示的结果状语从句）来替换。
The boy is so old that he can go to school.
I’m so tall that I can reach the top of the tree.
2. 此句是否定句式时，既可以用so…that…引导的结果状语从句来替换，还可以用too…to…句式替
换。例：
He is not old enough to go to work.
他太小不能去上班。
He is so young that he can’t go to work.
He is too young to go to work. 再如：
The box is not light enough for me to carry.
这个箱子太重我搬不动。
The box is too heavy for me to carry.
The box is so heavy that I can’t carry it.
四. sb. +be ready + to do sth. （某人乐意做某事）
He is always ready to help others.
（他总是乐于帮助别人）
I’m always ready to make new friends.
我总是乐于结交新朋友。
五. It’s +adj. + for / of sb. to do sth.
对某人来说做某事…例：
It’s dangerous for children to play football in the street.
对孩子来说在街上踢足球是很危险的。
It’s good for us to take more exercise.
对我们来说多运动是有益的。
It’s very kind of you to say so.
你这样说真是太好了。
It’s very kind of you to help me.
你真好，肯帮我。
该句式中，引导动词不定式的逻辑主语的介词用for还是of，主要取决于前面的形容词。如果形容词是描述动词不定式的行为者的性格、品质的。如：kind, good, nice, wrong, right, clever, careless, foolish等，应用of；如果形容词仅仅是描述事物，不是对动词不定式的行为者的品质进行评价的，就用for. 常见这类形容词有difficult, easy, hard, important, dangerous等。
It’s wrong of you to do it.
你做这件事是错的。
It’s hard for you to be a lawyer.
对你来说做律师很困难。
六. 主+would like / love to do sth. …喜欢（想做某事）
I’d like to go there with you.
我很想和你一起去那。
I’d love I like to help you study English.
我很愿意帮你学英语。
此句式还可以扩展为：
would like / love sb. to do sth.
“喜欢/想让某人做某事。”
I’d like you to stay here.
我想让你留在这。
I’d like them to help me.
我想让他们帮助我。
七. had better do sth. （…最好做…）
It’s very cold outside, you’d better put on your coat.
外面很冷，你最好穿上大衣。
We’d better go right now.
我们最好马上去。
…had better do 的否定式为…had better not do. （在better后加not即可）例： You’d better not speak when your mouth is full of food.
满嘴食物时你最好别讲话。
八. Why don’t you +动词原形+…？（Why not＋动词原形…？）你为什么不…？
这本书有点难，为什么不读些容易的？
This book is a bit hard, why not read something easier?
It’s warm here, why don’t you take off your coat?
这很暖和，你为什么不脱掉外衣？
There is a seat, why not sit down?
还有座位，怎么不坐下？
九. Would / Will / Could you please ＋动词原形＋…？
请你…好吗？（用来请求对方为自己做某件事）
Would you please bring some water with you?
请你带点水来好吗？
Will you please help her with her maths?
请你帮她学数学好吗？
十. …prefer …to do sth. rather than do sth. …宁愿…也不愿…
I prefer to stay at home rather than go out.
我宁愿呆在家里，也不愿出去。
She prefers to be poor rather than get money in such a way.
她宁愿受穷也不愿以这种方式挣钱。
十一. It’s one’s turn to do sth.
该轮到谁做某事了。
one’s用形容词性物主代词或名词所有格来替换。例：
It’s my turn to be on duty.
该轮到我值日了。
It’s Li Ping’s turn to clean the blackboard.
该轮到李平擦黑板了。
It’s our turn to do the cleaning.
该轮到我们做扫除了。
It’s Danny’s turn to give a talk.
该轮到Danny做报告了。
十二. 主语＋be＋形容词＋to do sth. …做某事如何。例：
I’m sorry to hear that.
听到这事很难过。
I’m glad to see you again.
再次见到你我很高兴
G
1. The teacher told them ________ make so much noise.
A. don’t
B. not
C. will not
D. not to
2. Our master often told us _______ things for granted.
A. not to have
B. not to take
C. didn’t take
D. not to make
3. Tell him _______ the window.
A. to shut not
B. not to shut
C. to not shut
D. not shut
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
5. Mrs Smith warned her daughter ________ after drinking.
A. never to drive
B. to never drive
C. never driving
D. never drive
6. The patient was warned _______ oily food after the operation.
A. to eat not
B. eating not
C. not to eat
D. not eating
7. The workers want us ________ together with them.
A. work
B. working
C. to work
D. worked
8. 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
9. I saw him _______ out of the room.
A. go
B. had gone
C. has gone
D. goes
10. They knew her very well. They had seen her _______ up from childhood.
A. grow
B. grew
C. was growing
D. to grow
11. I’ve heard him _______ about you often.
A. spoke
B. speaks
C. speak
12. 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
13. He was made _________.
A. go
B. gone
C. going
D. to go
14. John was made _______ the truck for a week as a punishment.
A. to wash
B. washing
C. wash
D. to be washing
15. Paul doesn’t have to be made _______. He always works hard.
A. learn
B. to learn
C. learned
D. learning
16. There’re so many kinds of tape-recorders on sale that I can’t make up my mind _______ to buy.
A. what
B. which
C. how
D. where
17. There isn’t any difference between the two. I really don’t know _________.
A. where to choose
B. which to choose
C. to choose what
D. to choose which
18. “ Have you decided when ________?”
“ Yes, tomorrow morning.”
A. to leave
B. to be leaving
C. will you leave
D. are you leaving
19. Last summer I took a course on ________.
A. how to make dresses
B. how dresses be made
C. how to be made dresses
D. how dresses to be made
20. He doesn’t know ______ to stay or not.
A. whether
B. if
C. either
D. if he will
21. She pretended _______ me when I passed by.
A. not to see
B. not seeing
C. to not see
D. having not seen
22. --- The light in the office is still on.
--- Oh, I forgot _______.
A. turning it off
B. turn it off
C. to turn it off
D. having turned it off
23. We agreed _________ here but so far she hasn’t turned up yet.
A. having met
B. meeting
C. to meet
D. to have met
24. Little Jim should love _______ to the theatre this evening.
A. to be taken
B. to take
C. being taken
D. taking
25. I would love ______ to the party last night but I had to work extra hours to finish a report.
A. to go
B. to have gone
C. going
D. having gone
26. Frank is the kind of person who people like to ________.
A. make friend with
B. make friends of
C. make friends
D. make friends with
27. Go on ________ the other exercise after you have finished this one.
A. to do
B. doing
C. with
D. to be doing
28. 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
29. Tom kept quiet about the accident ________ lose his job.
A. so not as to
B. so as not to
C. so as to not
D. not so as to
30. I need a day or two ________.
A. to think it over
B. to think over
C. of thinking
31. He was too excited _________.
A. speak
B. to speak
C. not to speak
D. speaking
32. Charles Babbage is generally considered ________ the first computer.
A. to invent
B. inventing
C. to have invented
D. having invented
33. He said he would rather not _______ it right now.
A. doing
B. to do
C. do
D. to be doing
34. Rather than _______ on a crowded bus, he always prefers _______ a bicycle.
A. ride； ride
B. riding； ride
C. ride； to ride
D. to ride； riding
35. It’s freezing outside. You _______ put on your overcoat.
A. had better to
B. had better
C. would better
D. would better to
36. The chair looks rather hard, but in fact it is very comfortable to _______.
A. sit
B. sit on
C. be sit
D. be sat on
37. I’m hungry. Get me something _________.
A. eat
B. to eat
C. eating
D. for eating
38. --- 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
39. She did nothing _______ at the photo.
A. except look
B. but to look
C. except to look
D. but looking
40. I asked him to _______ me a few minutes so that we could go over all the problems.
A. spend
B. spare
C. save
D. share
41. They won’t let their teacher _______ in that way.
A. to be treated
B. being treated
C. treated
D. be treated
42. John, you must get your room ________ after breakfast.
A. to be cleaned
B. to clean
C. cleaning
D. cleaned
43. The problem _______ at tomorrow’s meeting is a very difficult one.
A. being discussed
B. discussed
C. to be discussed
D. to discuss
44. He reached the station _____ only _____ that the train had just left.
A. tired； learned
B. tiring； learning
C. to tire； to learn
D. tired； to learn
45. --- Did that book give the information you needed?
--- Yes, but ______, we had to read it almost entirely.
A. for finding it
B. to find it
C. finding it
D. by finding it
46. I’m sorry I forgot ______your dictionary. Let’s borrow one from Li Ming.
A. to take
B. taking
C. to bring
D. bringing
47. She couldn’t decide which restaurant _______.
A. to have lunch
B. to eat
C. to eat at
D. eating at
48. This problem is said _____ three times.
A. to have been talked
B. to have discussed
C. having been discussed
D. to have been talked about
49. Everybody believed the man ______ away the diamond ring.
A. be taken
B. taking
C. to take
D. to have taken
50. I prefer ____ rather than ______.
A. read； watch
B. to read； watch
C. reading； to watch
D. to read； to watch
51.______in the matriculation for postgraduate in a short time is really a hard nut．A．To make high scores B．Making high scores
C．To make low goal D．Making low goal
[参考答案]
1-5 DBBAA 6-10 CCAAA 11-15 CADAB 16-20 BBAAA
21-25 ACCAB 26-30 DACBA 31-35 BCCCB 36-40 BBDAB
41-45 DDCDB 46-50 CCDDBA
解析：
1．tell sb. not to do sth告诉某人不做某事
2．take sth for granted “把某事想当然”，是一个固定词组。Eg. You shouldn’t take it for granted that everyone should help you.你不要认为每个人都理应帮助你。
4. 不定式的省略要保留到to,否则就完整地表达，如:…but his mother told him not to do so.
5. warn sb not to do sth. 此处用never替代not.
8. allow sb to do sth允许某人做某事；risk doing sth冒险做某事
9. see sb do sth看见某人做某事
12. make sb do 让某人做某事，但用于被动结构后，则要用不定式符号to连接。
16．which 用于有范围中的“哪一个”，此处作buy的宾语。
18．when +to do 做decide的宾语，若用when引导宾语从句，用陈述句语序。
21. pretend to do 假装做某事。
22．forget to do sth忘记（要）做某事。
24．should love to be taken to …愿意被带去……
25．因为状语是last night，用不定式的完成式表示本想……
27. go on to do sth. 继续做（与原来不相同的）事。此句可以从the other exercise 断定。
28．stop to do sth. 停下来（去）做……
32．被动语态后用不定式连接，根据句意用完成式。
33. would rather not do sth. 宁愿不做某事。
34. prefer to do sth. rather than do sth. 宁愿做……不愿做……
37．to eat 此处作something 的定语。for+doing多表用途。
38. why not do sth…“为什么不……”；try doing sth试一试
39．Do nothing but do sth, 此处用except替代but
40. spare sb. sth匀出、腾出……，宾语为sb.； share分享，宾语为sth.
41. let sb do, 此处用的是被动语态
42． get sth. done让某事被做
44．tired此处是过去分词，表示主语的状态。only to learn…此处的不定式表结果。
45．此处的to find it, 表示目的
47. to eat at the restaurant, 介词at不能丢
48. 此处使用的是不定式的完成被动式。表示“曾经被讨论过三次”。
高中英语语法讲解不定式 （The Infinitive） 定义：动词不定式是非谓语动词的一种，它没有人称和数的变化，在句子中不能独立作谓语，但它仍保持动词的特点，既可以有自己的宾语和状语。 E.g. He want his students to read the book aloud. A． 1不定式的构成（以动词do为例） 2 不定式的意义 不定式的一般式(to do ) 一般式表示的动作或状态，发生在谓语动词表示的动作或状态的同时或之后My wish is to become a doctor He seemed to be tired. She stopped to have a rest. 不定式的被动式 (to be done) 当不定式的逻辑主语是这个不定式所表示的动作的承受者时,不定式一般要用被动式. The building to be finished next month is for our teachers. I am going to Beijing, I have something to take to my parents, do you have something to be taken to your parents? 如果谓语表示的动作(情况)发生时, 不定式表示动作正在进行,这时候不定式就要用进行式.（to be doing） They are said to be building another bridge across the street. They seemed to be talking about something important. When I went to his home, he happened to be traveling around the world. I’m glad to be working with you. 如果不定式所表示的动作或状态发生在谓语动词所表示动作或状态之前，就用完成式 (to have done) ；若是在此基础上的被动含义，就用完成被动式( to have been done). He is said to have written a novel about the Long March. He thought it a pity not to have invited us. The assistant seemed to have been fired. He is said to have been taught French when he was a child. Einstein is said to have built up his theory when he was in his twenties. 如果不定式的动作是在谓语所表示的时间之前一直在进行的动作，就要用完成进行式. They are said to have been collecting folk song in Xinjiang. We’re happy to have been working with the experts all the month.
专题十六倒装句和省略句重难点分析 一、倒装句 倒装句主要考查以下几个方面： ◆含有否定意味的词置于句首，用部分倒装； ◆“only+状语/状语从句”置于句首，用部分倒装； ◆so/such…that句型中，“so+形容词/副词”提前，用部分倒装； ◆表示方位的副词或介词短语放在句首，要用完全倒装。 1. 倒装句用法一览表：
2. 特别提示 (1) there be结构的倒装句型中，除了be动词之外，there后还可接lie, live, seem to be等。如：There lived an old man in the village long long ago. 很久很久以前，村子里住着一位老人。 (2) here, there, now, then, up, down, away, out等副词位于句首，主语为代词时不到装。如：Away it flew. 它飞走了。 (3) 直接引语的一部分或全部位于句首，主句倒装，主句倒装，但是主语为代词时不倒装。如：“You have to finish it tonight,” she said. “今晚你必须完成它，”她说。 (4) so位于句首不倒装的情况：
① 主语与前句相同，表赞同，译为“确实如此”。如： — Mike studies hard. 迈克学习很刻苦。 — So he does. 确实是。 ② 表示前句内容也适用于另外的人或事，前句如果列举了两种事实以上，用“so it is/was with sb./sth.”回答。如： — Tom is kind and often helps those in trouble. 汤姆很友好，经常帮助处于困境中的人。 — So it is with his father. 他父亲也是。 (5) 使用as/though进行倒装时注意： ①句首有名词，名词不能带任何冠词。如：Child as he is, he can tell right from wrong. 尽管他是个孩子，却能够明辨是非。 ②句首是实义动词时，其他助动词则放在主语之后。如果实义动词有宾语和状语，则宾语和状语随实义动词一起放在主语之前。如： Try hard as he will, he never seems to be able to do the work satisfactorily. 虽然他尽力了，但他的工作总做得不尽如人意。 (6) not until位于句首的倒装结构中，如果是复合句，只有主句用倒装，从句不用。如： Not until he loses his health will he give up smoking. 他直到失去健康才会戒烟。 二、省略句 高考命题导向：省略是一种避免重复，保持简洁的语法手段。缺少一个或一个以上的必要语言成分，但在一定语境中能够独立存在，意义明确，并且能发挥交际功能的句子叫作省略句。高考主要是考查省略在固定结构中的运用。 省略句用法一览表：
高中英语倒装句 倒装句分为全部倒装和部分倒装 1全部倒装全部倒装是只将句子中的谓语动词全部置于主语之前。此结构通常只用于一般现在时和一般过去时。常见的结构有：1）here, there, now, then, thus等副词置于句首, 谓语动词常用be, come, go, lie, run等表示来去或状态的动词。例如：Then came the chairman. 那时总裁来了。Here is your letter. 你的信。 2). up，down，out，away，in , off, ahead放于句首Up jumped the cat and caught the mouse. Ahead sat an old woman. 3）表示地点，时间，方向等的介词短语放在句首时例如：After the head walked a group of workers. 4.“作表语的现在分词/过去分词/形容词+系动词+主语”形式的完全倒装 Seated in the front were the guests. 注意：上述全部倒装的句型结构的主语必须是名词，如果主语是人称代词则不能完全倒装。例如： Here he comes. 他来了。Away they went. 他们走开了。 2部分倒装 部分倒装是指将谓语的一部分如助动词或情态倒装至主语之前。如果句子的谓语没有助动词或情态动词，则需添加助动词do, does或did，并将其置于主语之前。 1. 句首为否定或半否定的词语，如no, not, never, seldom, little, hardly, rarely, scarely, in no way, under no circumstance, at no time决不, not until…等。例如： Never have I seen such a performance. 从未见过如此糟糕的表演。 Nowhere will you find the answer to this question. 无论如何你不会找到这个问题的答案的。 Not until the child fell asleep did the mother leave the room. 母亲一直到孩子入睡后离开房间。 当Not until引出主从复合句，主句倒装，从句不倒装。注意：如否定词不在句首不倒装。例如： The mother didn\'t leave the room until the child fell asleep. 典型例题 1）---Why can\'t I smoke here? ----At no time___ in the meeting-room A. is smoking permitted B.smoking is permitted C. smoking is it permitted D.does smoking permit 2）Not until the early years of the 19th century ___ what heat is. A. man did know B. man know C. didn\'t man know D. did man know 2.Not only…but also前面倒装，后面不倒装 Not only did he refuse the gift, he also severely criticized the sender. 他没有收下礼物，还狠狠批评了送礼的人。 3．Hardly/Scarcely…when, No sooner…than等，要倒装。 Hardly had she gone out when a student came to visit her. No sooner had she gone out than a student came to visit her. 典型例题No sooner___ than it began to rain heavily. A. the game began B.has the game begun C. did the game begin D.had the game begun 4so, neither, nor作部分倒装 so/neither/nor+be/can(should/will/could…..)/do(did/does)+sb表示\"也\"、\"也不\" 的句子要部分倒装。例如： 典型例题---Do you know Jim quarrelled with his brother? ---I don\'t know, _____. A. nor don\'t I care B. nor do I care C. I don\'t care neither D. I don\'t care also 注意：当so引出的句子用以对上文内容加以证实或肯定时，不可用倒装结构。意为\"的确如此\"。例如： Tom asked me to go to play football and so I did. ---It\'s raining hard.---So it is. 5 only在句首后接状语用总分倒装。例如： Only in this way can you learn English well. 只有这样，你才能学好英语。 如果句子为主从复合句，则主句倒装，从句不倒装。例如： Only when he is seriously ill does he ever stay in bed. 病得狠重时，他才卧床休息。 注意：如果only后的词组不是状语，不需倒装。
倒装句 英语句子的主语通常位于谓语动词之前，这种语序被称为正常语序。但有时出于强调或某种特殊的语法结构的需要，需要将谓语动词放在主语之前，这种语序则叫倒装语序。按倒装的形式，倒装可分为两类，一是完全倒装，二是部分倒装。完全倒装是指全部谓语放在主语之前，部分倒装是指只把助动词、情态动词或be动词放在主语之前，谓语的主体部分仍在主语之后。 一、完全倒装 1. 用于there be 句型。 例：There are many students in the classroom. 原句自然顺序是：Many students are there in the classroom. ★2. 表示地点的here和 there位于句首时，其后用完全倒装形式。这类倒装句的谓语通常是动词be和come, go等表示移动或动态的不及物动词，以及stand, lie, live等表示状态的动词(表示存在)。 例：Here comes the bus. 公共汽车来了。 There goes the last train. 最后一班火车开走了。 There stood a desk against the wall. 靠墙放着一张书桌。 注意：若主语为人称代词，则不倒装。如： Here you are. 这就是你要的东西。（给你。） Here it comes. 它来了。 ★3. 表示方向的副词away, down, in, off, out, over, round, up 等位于句首时，其后用完全倒装语序。这类倒装句的谓语通常表示动态的不及物动词。 Out rushed the puppy. 小狗冲了出去。 Away went the girl. 那个女孩走远了。 Down came the rain and up went the umbrellas. 下雨了，伞都撑起来了。 注：若主语为人称代词，则不能用倒装。如： In he comes. 他走了进来。 Down it came. 它掉了下来。 ★4. 表示时间或顺序的副词now, then 等位于句首时，其后用完全倒装语序。这类倒装句的谓语通常表示动态的不及物动词。如：
高中英语语法系统全解 第一章动词时态 在英语中，不同时间发生的动作或存在的状态，要用不同的动词形式来表示，这就叫做动词的时态。一、一般时 一般时包括一般现在时、一般过去时、一般将来时和一般过去将来时。 A.一般现在时 1．一般现在时的构成 一般现在时主要用动词原形来表示。主语是第三人称单数时，动词后面要加-s 或-es。 They want good jobs. 他们想要好的工作。 The coat matches the dress. 外衣和裙子很相配。 This work does not satisfy me. 这项工作我不满意。 Do you understand? 你懂了吗? 2．一般现在时的用法 ①一般现在时的基本用法 a. 表示现在习惯性的动作或存在状态 He always takes a walk after supper. 晚饭后他总是散散步。 Everyone is in high spirits now. 现在大家都情绪高涨。 b. 表示客观事实或普遍真理 The sun rises in the east and sets in the west. 太阳从东方升起在西方落下。 Sound travels faster through water than it does through air. 声音在水中的传播速度要比在空气中快。
Time and tide wait for no man. 时间不等人。 c. 表示主语的特征、能力和状态 This cloth feels soft. 这布摸上去很软。 I love classical music. 我喜欢古典音乐。 The President still seems able to find time to go fishing. 看来总统仍能有时间去钓鱼。 d. 表示按计划或安排将要发生的动作 The meeting begins at 7:00. 会议七点钟开始。 We leave here at 8:00 sharp. 我们八点整离开这里。 e. 在时间、条件、让步状语从句中表示将来动作 When you come next time, bring me some magazines. 你下次来时，给我带几本杂志。 If time allows, we shall go there tomorrow. 如果时间允许的话，我们明天去那里。 Whether he agrees or not, I will stay at home. 不管他同意与否，我都会待在家里。 ②一般现在时的特殊用法 a. 用于新闻标题或图片说明中 China Declares Manned Spaceflight Successful 中国宣布载人航天飞行圆满成功 Laura Bush Arrives in Moscow 劳拉·布什抵达莫斯科 b. 用于体育运动、表演等实况报道中 Francis slips past, passes the ball to Yao Ming, who jumps, catches and shoots it into the basket.
巧记跟不定式和动名词做宾语的动词用法 语法体现语言的规律,学好英语离不开语法学习。其中，动词的用法是重点，也是难点。对于谓语动词和非谓语动词的用法，学生普遍感到困难。学生感到50多个动词，用法难以掌握，但调整了单词的排列顺序，根据汉意编写顺口溜会方便记忆： （一）跟不定时作宾语的动词有： 打算(intend)计划(plan)和期盼(expect/desire) 假装(pretend)喜欢(would like/love/prefer)表祝愿(wish) 决定(decide)同意(agree)来帮助(help) 设法(manage)说服(persuade)不拒绝(refuse) 好像(seem/appear)答应(promise)做努力(attempt) 选择(choose)询问(ask)多学习(learn) 告诉(tell)失败(fail)也付得起(afford) 不定式宾语要牢记！ （二）跟动名词作宾语的动词有： 考虑（consider）完成（finish）多练习（practise） 避免（avoid）冒险（risk）求建议（suggest/recoomend） 面对（face）喜欢（enjoy/appreciate）和介意(mind) 允许（allow）承认（admit/permit）或放弃(give up/abandon) 推迟（put off/delay/postphone）逃避（escape）不原谅（excuse/pardon）提及（mention）坚持(keep/insist on）要想象（imagine/fancy） 还有词组feel like 和can’t stand！ 瞧！，我们就这样快快乐乐地记住了吧！ （三）在动词remember, try, regret, forget, need/want/require， stop, mean等后跟动名词V-和不定式意义不同，巧记一句话（记住努力；后悔忘记；需要停止；很有意义），学习采用对比法： remember to do something记着去做某事（现在还没有做） remember doing something记着曾做过某事（以前做过某事） try to do something努力、尽力做某事 try doing something试着做某事（看能否达到预期的结果） stop to do something开始做某事（停下正在做的事，开始做另一事） stop doing something停止做某事（停止正在做的事） regret to do something对将来做的事感到遗憾、惋惜 regret doing something对已经做过的事感到后悔
人教版高中英语必修二 知识点梳理 重点题型（常考知识点）巩固练习 限制性定语从句和非限制性定语从句 概念引入： He is a person who never gives up. 他是个永远不服输的人。 I found him in the woods, where has a well-known tree. (我是在树林里找到他的，那里有一棵很有名的树。) Our guide,(who was a Frenchman, ) was an excellent cook. 我们的导游是个很优秀的厨师，他是个法国人 She was not on the train which arrived just now。 她没在刚刚到达的那辆车上 语法点拨 什么是定语从句？ 修饰主语、宾语、表语的句子就叫做定语从句。引导定语从句的关系词有： 关系代词：who, whom, whose, which, that 关系副词：when, where, why 我们把下面两个句子组合成一个复合句： 1. This is our school. It is beautiful. →This is our school which is beautiful. 2. This is our school. We study in our school. →This is our school which we study in. →This is our school in which we study. →This is our school where we study. 3. Do you know the room? It is made of amber. →Do you know the room which is made of amber? 4. I have read the newspaper. It carries the important news. →I have read the newspaper which carries the important news. 从上述定语从句的组合我们可以看出： 先行词和关系词的关系：关系代词实际上是先行词的复指；关系词whose 实际上是先行词的所有格。 1. A plane is a machine that can fly. the machine = that 2. The boy who broke the window is called Wangkai. the boy =who 3. The boy whose parents are working outside was brought up by his grandfather. the boy’s =whose 【高一英语语法（二）定语从句（二）356521限制性定语从句和非限制性定语从句】
高中英语倒装句语法知识汇总 一.概念: 英语句子通常有两种语序:一种主语在前,谓语在后,称为自然语序,另一种谓语在前,主语在后,称为倒装语序。 二.相关知识点精讲 按“主语+ 谓语” 这种顺序排列的句子是陈述语序。如果排列顺序变为“谓语（或谓语一部分）+主语”，就是倒装。倒装句分为： 完全倒装：整个谓语移至主语前面叫完全倒装。 部分倒装：只把助动词、系动词或情态动词放在主语之前叫部分倒装。 1. 当以there, here, out , in , up , down, away 等副词开头的句子，为了起到强调的作用，可构成倒装句，只把副词放在句首，主语和谓语位置调换，不加助动词。 Our teacher came in. In came our teacher. 这种倒装要求：主语必须是名词。主语是人称代词时，主语和谓语语序不变。 Here it is. Away he went. 这类倒装句式一般只用一般现在时和一般过去时。 Here comes the bus. Out rushed the boys. 2. how, then, just, often 表示时间的副词放在句首，可构成倒装句，只把副词放在句首，主语和谓语位置调换，不加助动词。 Then came 8 years of the Anti Japanese War. 3. 表地点状语的介词短语放在句首，要用倒装句式，以示强调。 这种倒装句也是主谓直接调换位置，不加助动词did, does或do. Under a big tree ________, half asleep. A. did sat a fat man B. a fat man sat C. did a fat man sat D. sat a fat man 4. there放在句首时，要用倒装句式。 在“there + be”结构中的谓语动词有时不用be , 而用表示类似“存在”观念的其他不及物动词。如：live, stand, come, lie, flow, enter, rise 和appear等。 There came shouts for help from the river. There lies a large wheat field in front of the house. Many years ago there lived an old man in the wooden house. In front of the tower flews a stream. 5. so + 动词+主语 neither/ nor + 动词+主语 表示两人的同样一个情况时，只能表示一件事，即上、下句所使用的动词、时态要一致。 否则要用so it is with… You can ride a bike. So can I . He has been to Beijing. So have I . The first one isn’t good, neither is the second. His uncle is a worker and has been working in the factory for more than ten years. So it is with his aunt. 6. so+ 形容词/副词that 的结构状语从句可以用正常语序表示，也可以把so+形容词/副词放于句首构成倒装。句型如下：so +形容词/副词+be/助动词/情态动词that +从句。 Light travels so fast that it is difficult for us to imagine its speed. = So fast does light travel that it is difficult for us to imagine its speed. So easy was the work that they finished it in a few days. 7. done做形容词在句中做表语时，常把表语放在句首，要用倒装句式。 Gone forever are the days when the Chinese people had to use foreign oil. 8. 否定副词not , never, seldom, nowhere, little , rarely 放于句首时要用倒装句式。 We seldom get up at four in the morning. = Seldom do we get up at four in the morning. Not a single word from him could the enemy drag.
必修一 语法点一：Be+v.ing表将来 use the present continuous tense for future plans In English, we have lots of ways of talking about the future. The most common ways of talking about the future we encounter use ‘will’ or ‘be going to’ followed by an infinitive（动词原形）, and we tend to use ‘be going to’ most often for talking about future plans. Sometimes, we also use the present continuous tense to talk about future plans. Ex. ①we are going to Mexico next Sunday. ② Are you coming to the cinema? ③ He is leaving for London in two hours. ④ We are spending next winter in Australia. Only some verbs can be used in this situation, such as: go, arrive, come, leave, start, stay, return, play, have, work, wear, spend, see, meet, etc. 扩展： What’s the difference between using ‘be going to’ and the present continuous to talk about future plans? Let’s look at some more examples: “I’m going to play football on Saturday” You have made a plan in your head but possibly not taken any real action to confirm it. Also, playing football on Saturday is probably not a regular event for you. “I’m playing football on Saturday” You have made a plan and taken some real action to confirm it (e.g. called your friends or booked a place to play). In this case, it’s likely that playing football on Saturdays is a common activity for you. 语法点二：Direct speech and indirect speech(直接引语和间接引语) Let's first define the terms, then look at how to talk about what someone said, and how to convert speech from direct to indirect or vice-versa. You can answer the question What did he say? in two ways: by repeating the words spoken (direct speech) by reporting the words spoken (indirect or reported speech). Direct speech repeats, or quotes, the exact words spoken. When we use direct speech in writing, we place the words spoken between quotation marks (" ") and there is no change in these words. Reported or indirect speech is usually used to talk about the past, so we normally change the tense of the words spoken. We use reporting verbs like 'say', 'tell', 'ask', and we may use the word 'that' to introduce the reported words. Quotation marks are not used. 1、declarative sentence陈述句 ①Change in pronoun:The pronoun (subject) of the reported speech is changed according to the pronoun of reporting verb or object (person) of reporting verb (first part of sentence). Sometimes the pronoun may not change. In following example the pronoun of reported speech is “I” which will be changed
倒装句 倒装的两种考法： 1. 放在单项选择题中，考查考生的倒装语法知识是否熟练掌握； 2. 放在完形填空和阅读理解中，设置理解障碍。 倒装的两种形式： 1. 完全倒装：将整个谓语动词提到主语前。 2. 部分倒装：即半倒装，将谓语的一部分即助动词提到主语前。 一、完全倒装 1】表方位的副词here, there 或out, in, up, down, away, off, over, back等标志词放在句首，句子用完全倒装。 【翻译句子】 (1)车来了。Here comes the bus. (2)铃响了。There goes the bell. (3)孩子们冲出来了。Out rushed the children. (4)那个男孩离开了。Away went the boy. 【疑难】 Here it is. In she came. Away he went. 【疑难剖析】当主语是人称代词时，主谓语序不变。 2】地点状语放在句首且谓语动词为come, live, lie, go, sit, stand等时用完全倒装。【完成例句】 (5)河的南面有一家小工厂。In south of the river lies a small factory. (6)山谷里传来一声喊叫。From the valley came a cry. 3】such, the following等放句首时，句子要完全倒装。 【翻译句子】 (7)Such are the facts. 情况就是如此。 (8)生活就是这样。Such is life. (9)The following is the answer to the question. 这个问题的答案如下。 4】There lie / exist / stand / live ＋主语＋…是there be 句型的变式 【翻译句子】 (10)山顶上有一幢高楼。There is a tall building on the top of the mountain. (11)山顶上耸立着一座古塔。There stands an ancient tower on the top of the mountain. 5】“表语＋系动词＋主语”的结构。 【例句观察】 Present at the party were Mr. Green and many other guests. 出席晚会的有格林先生，还有一些别的宾客。 Seated on the ground are a group of young men. 坐在地上的是一群年轻人。 【注意】此时，主语较长，可还原为正常语序即：主＋系动词＋表语。 二、部分倒装
Compiled by Ma Junqi 倒装句 英语句子的主语通常位于谓语动词之前，这种语序被称为正常语序。但有时 出于强调或某种特殊的语法结构的需要，需要将谓语动词放在主语之前，这种语 序则叫倒装语序。按倒装的形式，倒装可分为两类，一是完全倒装，二是部分倒 装。完全倒装是指全部谓语放在主语之前，部分倒装是指只把助动词、情态动词或 be 动词放在主语之前，谓语的主体部分仍在主语之后。 一、完全倒装 1. 用于there be 句型。 例： There are many students in the classroom. 原句自然顺序是：M any students are there in the classroom. ★2. 表示地点的here 和 there 位于句首时，其后用完全倒装形式。这类倒装句的谓语通 常是动词be 和 come, go 等表示移动或动态的不及物动词， 动词 (表示存在 )。 例： Here comes the bus. 公共汽车来了。以 及 stand, lie, live 等表示状态的 There goes the last train. 最后一班火车开走了。 There stood a desk against the wall. 靠墙放着一张书桌。 注意：若主语为人称代词，则不倒装。如： Here you are. 这就是你要的东西。（给你。） Here it comes. 它来了。 ★3. 表示方向的副词away, down, in, off, out, over, round, up 等位于句首时，其后用完全 倒装语序。这类倒装句的谓语通常表示动态的不及物动词。 Out rushed the puppy. 小狗冲了出去。 Away went the girl. 那个女孩走远了。 Down came the rain and up went the umbrellas. 下雨了，伞都撑起来了。 注：若主语为人称代词，则不能用倒装。如： In he comes. 他走了进来。 Down it came. 它掉了下来。 ★4. 表示时间或顺序的副词now, then 等位于句首时，其后用完全倒装语序。这类倒装句的谓语通常表示动态的不及物动词。如：
高中英语动词不定式用法大全(名师总结必考语法知识点，值得下载) 英语动词的非谓语形式为三种：动词不定式、动名词和分词。非谓语动词没有人称和数的变化。 动词不定式是一种非谓语动词形式，其结构为“to＋动词原形”，其中to 不是介词，而是动词不定式的符号，称为小品词，动词不定式没有人称和数的变化。动词不定式和其后面的名词等构成不定式短语，在句子中可以用作主语、表语、宾语、补足语、定语、状语等。 一. 作主语例如： To be a doctor is hard. 做医生很难。 To learn English well is not easy. 学好英语不容易。 To say is to believe.眼见为实。 动词不定式（短语）作主语时，为了避免句子的头重脚轻，可以用“it”作形式主语，而把真正的主语－－动词不定式（短语）放在句子的后部。例如上面的句子可以表示为： It is hard to be a doctor. It is not easy to learn English well. 再如： It’s important to pla nt trees in spring. 如果动词不定式的动作是谁做的，可以在动词不定式前面加一个由介
词for引导的短语，称为不定式的复合结构。例： It’s good for us to read English aloud in the morning. 对我们来说每天早晨大声读英语是很有益的。 It is important for students to use English every day. 对学生来说每天使用英语是很重要的。 二. 作表语：（在形式上，位于系动词后的就是表语。从含义上讲，表语是回答主语“是什么”或“怎么样”的语法成分。） 动词不定式（短语）作表语常用于系词be的后面。例： His work is to drive a car. 他的工作是开车。 My job is to feed animals. 我的工作是饲养动物。 Her ambition is to be a doctor. 她的理想是当医生。 三. 作宾语 动词不定式（短语）可以放在一些动词后面用作宾语，能以动词不定式作宾语的动词有：begin, start, want, forget, remember, show, learn, like, hate, love, ask等。例： I want to tell you a story. 我想给你讲个故事。 They begin to work at eight every morning. 他们每天早晨8点开始工作。 Don’t forget to lock the door.别忘了锁门。 Would you like to go and have a picnic with us tomorrow?明天和我们一
省略句 一、如果从句的主语和主句的主语一致，且从句的谓语含有be动词的某种形式 （am/is/are/was/were），可同时省略从句的主语和be动词的某种形式。 1、when，while引导的时间状语从句 e.g. Do be careful when (you are) crossing the street. When/While (I was) on my way to work, I met her. 2、if，unless，once引导的条件状语从句 e.g. If (it is) properly treated, waste will do no harm to the environment. I’ll not go to the party unless (I am) invited. Once (you are) caught stealing in a supermarket, you will be punished. 3、though，although，whether，no matter whether/what/how/who等引导 的让步状语从句 e.g. He was happy, though/although (he was) poor.
Whether (she is) sick or well, she is always cheerful. No matter how/However hard the task (is), we must fulfill it in time. （注：从句的主语和主句的主语不一致时，只省略从句中的be动词形式） 4、as if，as though引导的方式状语从句 e.g. He rubbed his eyes and yawned as if/though (he was) waking up after a long sleep. He stood up as if/though (he wanted) to leave.（as if/though + to do表示一个将来的动作） 二、than，as引导的比较状语从句中的省略用法：当不同的主语进行比较时， 一般省略从句中的谓语；当从句中的主语与谓语（be动词除外）和主句中的主语与谓语相同时，通常省略从句中的主语和谓语，只保留比较部分。 e.g. He is taller than his brother (is). I have as much as confidence in you as (I have confidence) in him. 三、以if从句为代表的状语从句中的特殊省略用法：通常省略了it is，that is， there is/are。 e.g. If (it is) possible/necessary, this old temple will be rebuilt. If (that is) so, I will call you back at 5:00 pm. There are only a few books in our school library, if (there are) any. Ⅱ、定语从句中的省略用法 关系词的省略关系代词that，which，whom等在限制性定语从句中充当宾语且不位于介词之后时，可以省略；in which或that在先行词way后作方式状语从句时可省略。 e.g. The man (that/who/whom) you visited last night is my grandpa. I don’t like the way (in which/that) you treat the girl. Ⅲ、虚拟语气中if及should的省略 1、当条件状语从句中有were，had，should等时省略if，把它们提至句首，形 成倒装句。 e.g. If I were a teacher, I would be strict with my students. = Were I a teacher, I would be strict with my students. 2、Suggest，insist，order，require等表示建议、要求、命令的动词后接的名词 性从句中，谓语动词常用“should+动词原形”，should可以省略。 e.g. The doctor suggested that he (should) try to lose weight. Ⅳ、不定式符号to的省略 1、感官动词see，hear，feel，watch等和使役动词have，make，let等后接不 定式作宾语时，不定式省略to。 2、do nothing but，can’t help but等结构常接省略to的不定式。 e.g. We didn’t do anything but stay at home watching TV yesterday. Hearing the news, she couldn’t help but cry. 3、在特定语境中为了避免重复，当不定式再次出现时，在want，wish，hope，