高中語法——不定式
發(fā)布時間：2020-03-07 01:30:50瀏覽次數(shù)：52263
動詞不定式是動詞的一種非謂語形式，在句中不能單獨(dú)作謂語。動詞不定式具有動詞的性質(zhì)，它可以有自己的賓語和狀語，從而構(gòu)成動詞不定式短語。
它還可以有形式的變化，即一般式、進(jìn)行式、完成式和被動式。
同時，動詞不定式也具有非動詞的性質(zhì)，相當(dāng)于一個名詞、形容詞或副詞，可以在句中擔(dān)任主語、賓語、賓語補(bǔ)足語、表語、定語和狀語。
動詞不定式是由不定式符號to+動詞原形構(gòu)成，在某些情況下to也可省略。
不定式的一般式表示的動作通常與主要謂語的動作同時或幾乎同時發(fā)生，或是在它之后發(fā)生。
He appears to be very happy.
不定式的進(jìn)行式表示正在進(jìn)行的或與謂語動詞同時發(fā)生的動作。
It happened to be raining when I got there.
不定式的完成式表示的動作在謂語表示的動作之前發(fā)生。
I'm sorry to have lost your key.
不定式的完成進(jìn)行式表示的動作在謂語之前發(fā)生并且一直進(jìn)行著。
He was said to have been living in London for twenty years.
據(jù)說他在倫敦一直住了20年。
【比較】不定式的時態(tài)意義：
He is said to be studying abroad.
據(jù)說他正在國外讀書。（不定式的進(jìn)行式表示動作正在進(jìn)行）
He is said to have studied abroad.
據(jù)說他在國外學(xué)習(xí)過。（不定式的完成式表示動作已經(jīng)結(jié)束）
當(dāng)不定式邏輯上的主語是這個不定式表示的動作的承受者時，不定式一般要用被動形式。不定式的被動形式根據(jù)其與謂語動作發(fā)生的先后關(guān)系，有一般式和完成時兩種。
1、一般式to be done
These are the books to be given out to the students.
這些是要發(fā)給學(xué)生的書。
2、完成式to have been done
The novel is said to have been translated into many languages.
不定式的否定形式由not或never加不定式構(gòu)成。
We decided not to go out because of the bad weather.
由于天氣不好，我們決定不出去。
【注意】謂語動詞的否定和不定式的否定不同的意義：
I did not promise to wake him up.
I promised not to wake him up.
動詞不定式除了不能單獨(dú)作謂語外，幾乎能擔(dān)任句子中所有的句子成分。
不定式具有名詞的特征，可在句子中充當(dāng)主語。
To know oneself is difficult.
在很多情況下，人們通常用it作為形式上的主語，而把不定式移到謂語之后，使句子結(jié)構(gòu)顯得平穩(wěn)一些。
It's rude to turn your back to your teacher and refuse to answer.
背對著老師，拒絕回答問題是不禮貌的。
【注意】當(dāng)主語和表語都是不定式時，不能用形式主語代替動詞不定式。
To respect others is to be respected.
不定式作表語可以說明主語的具體內(nèi)容或表示目的。
His wish is to become an astronaut.
他的愿望是成為一名宇航員。
【注意】有些作表語的不定式，在結(jié)構(gòu)上是主動的，但在意義上卻是被動的。
不定式可以充當(dāng)部分及物動詞的賓語，也可以充當(dāng)but和except等介詞的賓語以及形容詞的賓語。
（1）不定式可以充當(dāng)部分及物動詞的賓語。
Father likes to listen to music in silence.
父親喜歡靜靜地聽音樂。
【必背】可接不定式作賓語的動詞有：
afford負(fù)擔(dān)得起
agree同意
aim以……為目標(biāo)
ask要求
attempt嘗試
begin開始
care喜愛
choose決定
continue繼續(xù)
decide決定
desire要求
determine決心
expect期待
fail不能
forget忘記
hate不愿
hope希望
intend打算
manage設(shè)法
mean打算
offer表示愿意
plan計(jì)劃
prefer寧愿
pretend假裝
promise答應(yīng)
refuse拒絕
remember記起
try努力
want想要
wish希望
（2）在feel, find, make, think,consider等動詞后，如果賓語帶有賓語補(bǔ)足語時，人們常常用it作形式賓語，而把真實(shí)賓語放在賓語補(bǔ)足語之后。
I found it possible to work out the problem without a computer.
我發(fā)現(xiàn)有可能不用計(jì)算機(jī)而解出這道題目。
（3）在表示“希望、打算”等動詞（如hope,expect, intend, mean, want等）的過去式后，可接動詞不定式的完成式來表示沒有實(shí)現(xiàn)的動作。
I intended to have called on you, but was prevented from doing so.
我原想來拜訪你的，但沒來成。
【提示】表示“原打算、原以為”還可以用這類動詞的過去完成時來表達(dá)。
I had expected to meet him here last night.
The teacher made no comments except to tell him to work hard.
老師除了叫他努力學(xué)習(xí)外，未做任何評價(jià)。
3、作形容詞的賓語
不定式作形容詞的賓語有兩種句型，一個是句子的主語是不定式的邏輯主語，另一個是句子的主語是不定式的邏輯賓語。
（1）句子的主語是不定式的邏輯主語。這類形容詞有able,afraid, angry, anxious, careful, clever, content, cruel, determined,disappointed, eager, foolish, fortunate, frightened, happy, impatient, glad,lucky, naughty, prepared, proud, ready, slow, shocked, sorry, surprised,willing等。
I am sorry to say that he is going from bad to worse.
很遺憾，他的情況每況愈下。
（2）句子的主語是不定式的邏輯賓語。這類形容詞有easy,hard, cheap,expensive, dangerous, difficult, funny, fit, impossible,interesting, nice, pleasant, simple, strange, useful等。
This problem is easy to solve.
這個問題很容易解決。
【注意】在這種結(jié)構(gòu)中，如果不定式是不及物動詞，則必須加上結(jié)構(gòu)或含義所需的介詞。
The river is dangerous to swim in.
不定式可以在“主語+謂語+賓語+賓語補(bǔ)足語”句型中充當(dāng)賓語補(bǔ)足語。在這一句型中，賓語是動詞不定式的邏輯主語。
1、在表示感覺的動詞后作賓語補(bǔ)足語，并且不定式都不帶to。這類動詞有：see,hear, feel, watch, notice, observe, look at, listen to等。
I heard them sing yesterday.
昨天我聽見他們唱歌了。
【注意】轉(zhuǎn)為被動語態(tài)時，原不帶to的不定式要變成帶to的不定式。notice和watch沒有被動語態(tài)。
We saw the car stop.
→The car was seen to stop.
我們看見這輛車停了下來。
2、在使役動詞后作賓語補(bǔ)足語，不定式不帶to。
這類動詞有：make,let, have等。轉(zhuǎn)為被動語態(tài)時，其后通常都用帶to的不定式（have沒有被動語態(tài)）。
有些動詞跟不定式作賓語補(bǔ)足語時省去了to，這些動詞有：一感二聽三讓四觀看。
四觀看：observe,see,watch,look at
She made him give up smoking.
3、在表示心理狀態(tài)的動詞后作賓語補(bǔ)足語。這類動詞有：consider,think, believe, discover, find, imagine, judge, suppose, prove等。這類動詞后的不定式通常是“to be+形容詞或名詞”結(jié)構(gòu)，think, consider, find后的tobe?？墒÷?。
We consider him (to be) a good teacher.
我們認(rèn)為他是一個好老師。
4、在表示情感狀態(tài)的動詞后作賓語補(bǔ)足語。這類動詞有：love,like, prefer, hate, want, wish, expect等。
I'd prefer you to leave him alone.
我希望你不要打擾他。
5、動詞advise,allow, ask, beg, command, tell, invite, force, oblige, get, help, encourage,persuade, permit, remind, request, order, warn, cause等后面，多接不定式短語作賓語補(bǔ)足語。
We don't allow such things to happen again.
我們不容許這種事情再發(fā)生。
【注意】hope,demand, suggest等動詞后面不能接不定式作賓語補(bǔ)足語。
（誤）I hope you to give me a hand.
（正）I hope you can give me a hand.
（正）I wish you to give me a hand.
（誤）He demanded me to be present at the meeting.
（正）He demanded that we should be present at the meeting.
（正）He required us to be present at the meeting.
（誤）Mr Li suggested her not to go there alone.
（正）Mr Li suggested that she should not go there alone.
6、動詞不定式也可作一些短語動詞的賓語補(bǔ)足語。
I'm waiting for James to arrive.
我正等著詹姆斯的到來。
【必背】這些帶介詞的短語動詞有：
call on號召
arrange for安排
long for盼望
wait for等待
depend on依靠
relyon指望
不定式作定語通常放在其修飾的名詞或代詞之后，和被修飾的名詞或代詞之間是主謂關(guān)系、動賓關(guān)系、同位關(guān)系和修飾關(guān)系。
The future to greet us will be bright.
On Sundays, he always has a lot of letters to write.
星期天，他總是有許多信要寫
【注意】由于動詞不定式與其修飾的詞之間往往有動賓關(guān)系，因此，如果該不定式是不及物動詞，其后應(yīng)有必要的介詞。
She has a child to take care of.
He broke his promise to write to his parents regularly.
他沒有遵守諾言定期給他父母親寫信。
4、修飾關(guān)系
Now it is time to begin our class.
不定式作狀語可以表示行為的目的、結(jié)果、原因、條件等。
1、表示目的
I'm saving up to buy a computer.
我在存錢買電腦。
【注意】有時為了強(qiáng)調(diào)或突出這種目的，也可以用inorder (not) to do,和so as (not) to do結(jié)構(gòu)（soas to do不可以置于句首）。
He shouted and waved in order to be noticed.
為了吸引注意，他又嚷嚷又揮手。
2、表示結(jié)果
He got to the station only to find the train had gone.
他趕到車站，發(fā)現(xiàn)火車已經(jīng)開走了。
【必背】不定式表示結(jié)果常見于下列句型。
Would you be so kind as to lend me your bicycle？
We are not such fools as to believe him.
He didn't run fast enough to catch the train.
He lifted a rock only to drop it on his own feet.
His eyesight is too poor to read such small letters.
【注意】too...to...結(jié)構(gòu)中的形容詞如果是eager,pleased, happy, ready等，動詞不定式不表示結(jié)果，也沒有否定的意思。
The boy was too eager to get a geography book.
He is too anxious to know the examination results.
I was a fool not to listen to you at that time.
我當(dāng)時不聽你的話，真是傻瓜。
4、表示條件
A man would be blind not to see that.
（一）不定式的復(fù)合結(jié)構(gòu)
動詞不定式的邏輯主語（即不定式動作的執(zhí)行者）通常是句子的主語或賓語。如果不定式的邏輯主語不是句子的主語，此時一般用“for +名詞（代詞）+不定式”來構(gòu)成不定式的復(fù)合結(jié)構(gòu)，這種復(fù)合結(jié)構(gòu)在句中可以做主語、賓語、表語、狀語、定語。
This box is too heavy for the little boy to carry.
“be +不定式”結(jié)構(gòu)可以表示將來發(fā)生的動作，常有以下兩種情況：
The room is to be locked.
We are to begin the work next month.
疑問詞who,what, which, when, where, how, why后加動詞不定式構(gòu)成不定式短語，它在句中可作主語、賓語和表語。
I don't know whether to go to the meeting or not.
（四）with/without+名詞+不定式結(jié)構(gòu)
“with/without +名詞+不定式”結(jié)構(gòu)在句子中通常起狀語的作用。
With so much work to do, I shall not be able to go to the cinema with you.
（五）It is +形容詞+ for/of sb + to do結(jié)構(gòu)
在“It is +形容詞+of sb +不定式”結(jié)構(gòu)中，形容詞往往表示人物的性格和特征，如kind,silly, good, unwise, clever, wrong, right, foolish, stupid, careless, rude,impolite, bold, thoughtful, honest, bad, sensible, naughty等。
在“It is +形容詞+for/sb +不定式”結(jié)構(gòu)中，形容詞通常表示事物的性質(zhì)，如important,possible, impossible, necessary, difficult, hard, reasonable等。
It's kind of you to think so much of us.
(=You are kind to think so much of us.)
It is good lf you to help me with my English.
（強(qiáng)調(diào)you的特征＝Y(jié)ouare good to help me.）
It is good for you to give up smoking.
（強(qiáng)調(diào)的是give up smoking這一行為＝For you to give up smoking is good.）
動詞不定式to do通常是不拆開的，但偶爾也可在不定式符號to和動詞原形之間插入一個副詞，構(gòu)成分裂不定式。
He was too ill to completely carry out that program.
有一些不定式短語可以作狀語修飾整個句子，也可被稱為插入語。
To be honest, we are not sure to find the girl in the forest.
說老實(shí)話，我們不能確保在森林里能找到那個女孩。
【必背】用作獨(dú)立成分的不定式：
to tell you the truth說老實(shí)話
to be frank 坦率地說
to begin with首先
to be brief簡言之
to make a long story short長話短說
to be exact精確地說
to say nothing of姑且不說
to conclude總而言之
to be sure誠然，固然
to do him justice說句對他公道的話
so to speak可以這么說
動詞不定式在句中究竟用主動還是被動，有時比較復(fù)雜，主要有下面幾種情況：
1、不定式做后置定語，和被修飾的名詞或代詞構(gòu)成邏輯上的動賓關(guān)系，但又和該句主語構(gòu)成邏輯上的主謂關(guān)系時。
Do you have anything to say on this question？
針對這個問題你有什么要說的嗎？
2、不定式作形容詞的賓語，和句子主語構(gòu)成邏輯上的動賓關(guān)系時。
The book is difficult to understand.
這本書很難理解。
3、There be結(jié)構(gòu)中，當(dāng)說話人考慮必須有人去完成某件事時。
There is nothing to worry about.
There is a lot of work to do.
There is a lot of work to be done.
有許多事情要做。（強(qiáng)調(diào)有許多事情必須做）
She has two letters to type.
She has two letters to be typed.
I hoped to have met him at the railway station, but he didn't turn up.
We would love to have gone to the match, but the tickets were all sold out.
The plane was to have taken off at 9, but something went wrong.
飛機(jī)原計(jì)劃九點(diǎn)起飛，但出現(xiàn)了一些故障。
不定式可用于感嘆句，含有驚異、不滿、惋惜或贊美等感情色彩。
To think that he should do this!
Oh, God,to see her dance !
To think that all the money has been wasted!
想想，所有的錢都被浪費(fèi)掉了！（表示不滿）
1、在口語中，動詞原形come和go后可接不帶to的不定式。
2、在why引起的一些問句中，疑問詞直接跟動詞原形或not+動詞原形。
為什么不加入我們？
3、在hadbetter, had best, would rather, would rather...than, would sooner, would sooner...than,cannot but, cannot choose but, cannot help but等結(jié)構(gòu)后直接跟動詞原形或not+動詞原形。
You'd better listen to your teacher's opinion.
We had best call for the doctor at once.
She can't do anything but ask silly questions.
Rather than ride on a crowded bus, he always prefers to ride a bicycle.
He cannot but move to another street, because his building has to be pulled downsoon.
他不得不搬到另一條街上去，因?yàn)樗〉拇髽呛芸炀鸵煌频埂?br />
We cannot help but admire his courage.
我們情不自禁地欽佩他的勇氣。
4、如不定式前有行為動詞do，那么在表語從句中的不定式和介詞except或but之后的不定式可不帶to。
The only thing I could do was go home.
They could do nothing but wait for the doctor to come.
他們只能等待醫(yī)生的到來。
5、在兩個動詞不定式并列使用時，為了避免重復(fù)，后面的不定式符號to可省略。
The little girl hardly knew whether to laugh or cry.
Can you help me to call him and ask him to attend the meeting at 2 p.m？
你能不能幫我打電話給他，叫他下午兩點(diǎn)來開會？
6、在help之后，既可用帶to的不定式也可用不帶to的不定式。
Can I help (to) carry the box for you？
我?guī)湍惆嵯渥?，好嗎?br />
7、在一些固定搭配中用不帶to的不定式。
I hear say there will be an earthquake soon.
She made believe she was innocent.
她假裝清白。
8、在感官動詞see,hear, watch, feel, notice以及使役動詞make,let, have等后作賓語補(bǔ)足語的動詞不定式不帶to。
She watched the children cross the street.
They made the boy apologize to his friend for being so rude.
Don't forget to have him come earlier.
為了避免重復(fù)上文中出現(xiàn)過的動詞，可以用不定式符號to來代替上文中出現(xiàn)過的不定式結(jié)構(gòu)。
1、在助動詞或情態(tài)動詞之后，如begoing to, used to, have to, ought to, be able to, be about to等。
She must go but you don't have to.
她必須走，但你沒有必要。
2、在want,decide, like, love, hope, wish, mean, refuse, try等動詞之后。
You may go with them if you hope to.
如果你希望的話，你可以和他們一起去。
3、在做賓語補(bǔ)足語的ask,tell, order, advise, persuade, warn, wish, permit, allow, forbid等動詞之后。
Don't do anything unless your father tells you to.
除非你父親叫你去做，不然不要做任何事情。
4、在對話的答語中的happy,glad, eager, anxious, willing, ready, pleased, afraid等形容詞之后。
—Will you lend me a hand？
—I'm willing to, but I can't now.
【提示】如果動詞不定式是tobe或to have，則一般不省。
—Did you finish the work？
to既可以是不定式符號，后接動詞原形；to也可以是介詞，后接名詞或動詞的-ing形式。英語中有很多常用短語帶有to，我們要正確判斷to是不定式符號還是介詞，千萬不可混淆。
1、不定式符號to
He made it a rule to read English aloud for half an hour every morning.
These young lads are longing to go to watch the football match.
be supposed to do應(yīng)該做某事
be determined to do決心要做某事
have the nerve to do有膽量做某事
have agreat mind to do很想做某事
make apoint to do堅(jiān)持做某事
make up one's mind to do決定做某事
take the trouble to do不辭辛苦地做某事
prepare oneself to do有思想準(zhǔn)備做某事
2、介詞to
If you stick to the truth, you will have nothing to fear.
You must get used to getting up early.
Isn't it time you got down to marking those papers？
難道還沒到你定下心來閱卷的時間嗎？
【必背】常見的帶介詞to的短語：
be used to習(xí)慣
be equal to勝任
be given to沉溺于
be opposed to反對
be related to與……有關(guān)
devote oneself to獻(xiàn)身于
get down to著手做
give rise to引起
lead to導(dǎo)致
look forward to盼望
object to反對
pay attention to注意
put one's mind to全神貫注于
stick to堅(jiān)持
