动词不定式

1、 动词不定式

其形式是“to+动词原形”。 to 是不定式符号，无词义。其否定式是在 to 前面加上 not, never等否定词。

不定式可以有自己的逻辑主语，由 for引出，加在不定式短语前面。

如果不定式的逻辑主语是表示不定式动作的承受者，则不定式用被动语态。所谓逻辑主语，就是指非谓语动词等动作的执行者。由于非谓语动词等带有动词的特征，但又不是谓语动词，所以这个动作的执行者就不能称为主语，而在逻辑上又是这个动作的执行者，所以就称为逻辑主语。

如果不定式逻辑上的主语是这个不定式所表示的动作的承受者，这个不定式一般要用被动语态。疑问词(who, whom, whose, what, which, when, where, why, how 还包括 whether)等后面加不定式构成不定式短语，可做主语，表语，宾语等。

(一)作主语。

在不定式短语作主语的句子中，往往用 it 作形式主语，而不把不定式短语放在句子的后面。如：

To die like that is a terrible thing.=It is a terrible thing to die like that.

象那样死去是一件可怕的事。( it 作形式主语，把真正的主语 to die like that 放在后面)

To know oneself is difficult.=It’s difficult to know oneself.

有自知之明不容易。

To tell a lie is not always easy.= It’s not always easy to tell a lie.

撒谎并非总是容易。

Never to offend anyone is my principle. 永远不得罪任何人就是我的原则。

It’s against nature to remain single. 保持单身是违反自然的。

To see is to believe. 眼见为实。

For a dog to die like that is a terrible thing. = It is a terrible thing for a dog to die like that.

一条狗象那样死去是一件可怕的事。(for a dog 是不定式的主语)

For one to know everything is impossible.= It’s impossible for one to know everything.

一个人什么都知道是不可能的。

For his brother John to go to sea seems natural.= It seems natural for his brother John to go to sea. 他兄弟John 去当水手是很自然的事。

It’ll be a great shame for you to forget her. 你要是把她忘了，那可太不应该了。

It’s not proper for us not to accept the invitation. 我们不接受邀请不合适。(否定)

It has not yet been decided when and where to discuss her resignation. 何时何地讨论她的辞职还没定。

但是，下列形容词做表语时，不定式的逻辑主语由 of 引出：

careless粗心的，clever聪明的，cruel 残忍的，foolish 愚蠢的，good 好的，kind 好心的 ，naughty淘气的，nice 好的，polite 礼貌的，right正确的，rude 无礼的，silly愚蠢的，stupid 傻的，unwise 不明智的，wise 明智的，wrong 错误的，等等。

为什么这些词要用 of 引出不定式呢?

因为这些形容词都是描写人的性格和特点的形容词。“It is + 形容词+of sb + to do sth”这样的句型更强调某人如何如何，可以改写为：“Sb + be + 形容词 + to do sth.” 而“for sb to do sth”这一结构更强调做某事如何如何。例如：

1、 It is difficult for me to learn English. 更强调学英语很难，不能写成

I am difficult to learn English. (这句话含有逻辑错误。)

2、 It is unwise of you to go to the United States at this time. =You are unwise to go to the United States at this time. 强调你不明智。

It’s very kind of you to come to see us off. =You’re kind to come to see us off. 你来为我们送行太好了。

It’s unwise of him to drink and smoke so much.=He is unwise to drink and smoke so much. 他喝这么多酒、抽这么多烟是不明智的。

It’s extremely cruel of John to kill animals. John 杀害动物真是残忍之极。

It’s rude/polite of Jack to say this to her. Jack对她说这个，很无礼/礼貌。

(二)作宾语及宾语补语。

1、有些及物动词常用动词不定式作宾语。常见的这类动词有：afford 负担得起，

agree 同意，arrange安排，ask 要求，attempt 试图，beg 乞求，begin 开始，choose选择，claim声称，consent 同意，dare 敢，decide 决定，decline 谢绝，desire 欲想，demand 要求，determine 决心，expect 期待，fail 失败，forget 忘记，hate 讨厌，help帮助，hope希望，intend打算，learn学习，like 喜欢，long 渴望，manage 设法，mean 打算，need 需要，offer主动提出，plan计划，prefer更喜欢，prepare 准备，pretend 假装，promise 答应，refuse 拒绝，remember记得，seek 寻求，seem好像，tend 倾向，threaten 威胁，undertake 承担，volunteer志愿，want 想要，wish 希望等。

I agreed to support him. 我答应支持他。

He said he wanted to be a professor. 他说他想当教授。

My daughter preferred to have eggs and milk for breakfast when she was in her twenties.

我女儿二十几岁时早饭喜欢吃鸡蛋和牛奶。

2、不定式可以和 how, which, what, who, whom, whose, when, where 还有 whether 等词连用作宾语。常跟这种结构作宾语的动词有：ask 询问，advise 建议，consider考虑，decide决定，discover 发现，discuss 讨论，explain解释，find out 查明，forget 忘记，inquire 打听，know知道，learn 学会，remember记得，show演示，tell 告诉，teach 教，think 想，understand 懂得，wonder想知道，等等。例如：

I don’t know where to get so much money. 我不知道去哪里搞这么多钱。

They haven’t decided whether to leave or stay. 他们还没决定是走还是留。

此外，这种不定式结构还可作主语，表语，和介词宾语等。

How to live a happy life is a difficult question to answer. 怎样过幸福生活是个很难回答的问题

The question is whom to choose for the position. 问题是这个位置选谁。

That was a discussion about how to increase their strength. 那是一次关于怎样增强他们力量的讨论。

He said nothing about what to do with her. 关于拿她怎么办，他啥也没说。

She asked my suggestion just now about where to go for her holidays. 关于去哪里度假，她刚才征求了我的意见。

3、有些动词需要不定式作宾语补足语。这种动词常见的有：ask 请求，advise 劝告，allow允许，beg

乞求，believe 相信，call on 号召，cause 促使，compel 强迫，command 指挥，direct 指导，enable 使…能够，encourage 鼓励，expect 期望，feel 觉得，force 迫使，get 使得，hate 不喜欢，have 使，hear 听见，help 帮助，inspire 鼓舞，intend 打算,invite 邀请,instruct 指示，know知道，lead 引导，let让，like 喜欢，listen to 听，look at 看，make 使得, notice 注意到, observe 观察，order 命令，permit 允许，persuade 说服，prefer 更喜欢，press施加压力，remind 提醒，request 请求，teach教，tell 告诉，urge 敦促，want 想要，warn 警告，wish希望，等等。

I asked my mother to buy a new bike for me. 我请求妈妈给我买辆新自行车。

Tony knew his girl friend to be a shy college student. 托尼知道他的女朋友是一个害羞的大学生。

They helped you to get on the bus, didn’t they? 他们帮你上了汽车， 是吗?

4、有些动词要求省掉 to 的不定式作宾语补语。这样的动词有：feel觉得，have使，hear听见，help 帮助，let 让，listen to 听，look at 看，make 使，notice 注意，see 看见，observe 观察，watch观看 等，一类是感官动词，一类是使役动词。

A policeman saw the accident happen. 一位警察看见事故发生。

We listened to her talk about her experience abroad. 我们听她讲国外的经历。

We’d be glad to have you work with us. 我们会很高兴有你和我们一起工作。

上述 help 后面的不定式省掉 to 与保留 to 都可以。在被动语态中，上述动词后面的不定式要把省去的to 还原。

I heard the dog come in. 我听见那条狗进来。

=The dog was heard to come in. 有人听见那条狗进来。

I saw her go out by bike. 我看见她骑着自行车出去了。

=She was seen to go out by bike. 有人看见她骑着自行车出去了。

Can I help (to) lift this heavy box? 我可以帮着搬起这个沉重的箱子吗?

You may as well help me (to)get things straight. 你不妨帮我把东西整理好。

She helped the old woman (to) cross the street. 他帮助那位老妇人过街

在 had better(最好)，would rather(宁愿)，would sooner(宁愿)，would (just) as soon(宁愿)，cannot but(不能不，不由得不)，cannot help but(不能不，不由得不)等成语后面也跟不带 to 的不定式：

He would rather listen to others than talk himself. 他宁愿听别人也不愿自己说。

He would sooner play than work. 他宁愿玩也不愿干活。

You had better go away right now. 你最好立即就走。

I would rather take this method. 我倒愿意采取这个办法。

I’d rather walk than take a bus. 我宁可走也不愿坐公共汽车。

She’d rather die than lose the children. 她宁可死也不愿失去孩子们。

I’d rather not have eggs and bacon for breakfast.

She’d sooner stay at home.

I would as soon do it by myself.

I would just as soon stay as go. 我宁愿住下也不愿去。

We couldn’t but weep at the sad news.

You can’t but respect them.

Rather than 和 sooner than同义，都是“宁可”，“与其…(不如)”，“不是…(而是)”的意思。当它们放在句首时，其后跟不带 to 的不定式;在其它位置时其后的不定式可带也可不带 t

Rather than risk breaking up his marriage, he told his wife everything. 他把一切都告诉了妻子，而不是冒离婚的危险。

Rather than cause trouble, he left. 他宁可走开而不愿引起麻烦。

Sooner than marry that man, she would earn her living as a waitress. 她宁可当女招待养活自己，也不嫁给那个男人。

He decided to write rather than telephone. 他决定写信，不打电话。

The manager believes it is important to invest in new machinery rather than to increase wages. 经理相信重要的是投资买新机器，而不是增加工资。

Rather than John do it, I’d prefer to do the job myself. 与其让 John 干这件事情，我宁可自己动手。

4、有些动词要求省掉 to 的不定式作宾语补语。

在 Why 起首的疑问句中跟不带 to 的不定式：

Why not come with us? 为什么不跟我们一起来呢? =Why don\' t you come with us?

Why not go for a game of tennis? 为什么不去打网球呢?

Why not relax yourself? 为什么不放松你自己呢?

Why not try to train your character? 为什么不培养你的性格呢?

Why not give the $40 to Tom? 干吗不把那 40 美金给汤姆呢?

For God’s sake, why bring that up again? 看在上帝的份上，干吗又提这事呢?

Why split hairs over the color of the dress? 干吗对连衣裙的颜色吹毛求疵呢?

Why run this risk? 干吗冒这个险?

Why risk breaking the law? 干吗冒犯法的险呢?

5、不定式作宾语而后面还有宾语补语时，常用 it 来代替不定式短语，而把真正作宾语的不定式短语

放在补足语后面。常见的动词有：consider 认为，feel 觉得，find 发现，make 使，think 认为，等等。例如：

I think it best to go. 我想最好走。

Do you consider it right to send our doctors over? 你觉得派我们的医生去对吗?

I found it strange for her not to come today. 我发现她今天没来是很奇怪的。

注意：hope 希望，demand 要求，suggest 建议，这三个词不能跟不定式作宾补。

错误的句子：

I hope you to be happy. 我希望你快乐。

I suggest you to take him seriously. 我建议你要把他当回事。

We demanded them to give us a definite answer.我们要求他们给个确切的答复。

正确的句子：

I hope that you’ll be happy. 我希望你快乐。I suggest that you take him seriously. 我建议你要把他当回事。

I advise you not to take him seriously. 我建议你不要把他当回事。

We demanded that they give us a definite answer. 我们要求他们给个确切的答复。

(三)作定语。

不定式短语作定语时，一般放在被修饰的词之后，有些名词的后面常用不定式作定语。常见的有：

ability能力，agreement 一致，协议，ambition 抱负、野心，anxiety 焦急，attempt 试图，campaign 战役，chance 机会，claim声称，courage 勇气，decision决定，determination 决心，drive 努力，eagerness殷切的心情，effort 努力，failure 失败，hope 希望，intention目的意图，motive force 动力，movement 运动、协议，need 需要，opportunity 机会，plan 计划，promise 诺言，readiness 乐意，refusal 拒绝，reluctance 勉强不愿，resolution 决心，tendency倾向，right权力，struggle 斗争，threat 威胁，time 时候，way 方法，willingness愿意，wish 希望。

与这些词相对应的形容词或动词常接动词不定式。如 ability →be able to, refusal →refuse to 等。

作定语时不定式表示将要发生的动作。

There is not any one to save him. 没有任何能救他的人。

He’s a not a man to tell lies. 他不是那种撒谎的人。

He’s a man to be trusted 他是个可以信赖的人。

He needs love to strengthen his broken heart. 他需要爱来给他那破碎的心以力量。

I don’t understand his idea to send his son to the Sahara. 我不明白他把儿子送到撒哈拉沙漠的想法。

I need to buy a box to hold my CDs. 我需要买个装 CD片的盒子。

This visit is a good opportunity to learn Chinese. 这次访问是学习中文的好机会。

No investigation, no right to speak. 没有调查就没有发言权。

Not to speak much is the best way to avoid trouble. 不多言是避免麻烦的最好办法。

This is a good way to make money. 这是个赚钱的好方法。

We were given some bread to eat. 给了我们一些面包吃。

I’ve a lot of things to take care of in the office today. 今天我办公室里由于很多事情要处理。

Have you got a key to unlock this door? 你有开这个门的钥匙吗?

He needs a place to live in. 他需要有个住的地方。

This is not a pen to write with but to draw with. 这不是写字而是画画用的笔。

I have not a friend to talk with. 我没有能谈心的朋友。

作定语时，也可以给不定式加上主语。例如：

The order for the army to start has been given. 已经发出了让部队开始的命令。

The power for science to serve mankind is limitless. 科学为人类服务的力量是无穷的。

The letter for you to answer is placed on your desk.. 要你回的那封信放在你办公桌上。

(四)作表语。放在系动词之后。

例如：

To gamble is to commit suicide, but not to get rich. 赌博就是自杀，而不是致富。

To criticize others is to make enemies. 批评别人就是树敌。

To do everything is to do nothing. 什么都做等于什么也做不成。

Perhaps the most popular way of relaxing is to participate in sports. 也许最受欢迎的放松方式就是参加体育活动。

This matter is for you to consider. 这个问题是要你考虑的。

These apples are for the guests to eat. 这些苹果是给客人们吃的。

My hope is for all members to come together once a year. 我的希望是所有成员每年聚会一次。

My advice is for you to apologize to her. 我的建议是你向她道歉。

The question is where to go for help. 问题是到哪里求助。

To respect others is to be respected. 尊重别人就是受到别人的尊重。

To see her is to love her. 见到她就会爱上她

(五)不定式短语和疑问词连用(who, whom, whose, what, which, when, where, how,还包括 whether)

(1)做主语。

例如：

Who to turn to is what she wants to know. 找谁帮忙是她想知道的。

It’s problem what to do. 干什么还是个问题。

How to be wealthy, healthy and happy will always remain a question mark. 怎样才能富有，健康和幸福将永远是个问号。

(2)做表语。例如：

The question is which to take first. 问题是先拿哪一个。

What remains for you to explain is how to put the plan into practice and whose help to seek. 剩下需要你解释的是怎样实施计划以及寻求谁的帮助。

The question is which of the methods to adopt. 问题是采取这些方法中的哪一个。

(3)作宾语，常用这一结构作宾语的动词有 ask, consider, decide discuss, explain, forget, find out, guess,inquire, know, learn, remember, see(=understand), show, settle(=decide), tell(=know), think, understand, wonder等。

I’ve found out where to buy them cheaply. 我发现了在哪里买这些东西便宜。

Do you remember when totch off the machine? 你记得什么时候关掉机器吗?

I can’t tell what to do . 我说不好怎么办。

How can you tell which button to press? 你怎么知道按哪个按钮?

You know very well when to say what and how to say it. 你很清楚什么时候说什么话以及怎样说。

He can’t decide what time to leave or whether to leave at all.他不能决定何时离开或者到底是否离开。

有些双宾语及物动词，也可用这个结构做直接宾语。常用的有 tell, inform, show, advise, ask, teach,等。

如：

I showed her how to use the remote control. 我向她演示怎样使用遥控器。

The salesman told him whichtch to turn on first. 售货员告诉他先开哪个开关。

Will you advise me which to buy? 你建议我买哪个?

Please inform me where to get the tickets. 请告诉我到哪里去弄票。

(4)做定语。例句:

I must find a pen with which to fill in this form(=to fill in this form with). 我必须找支钢笔填表用。

He offered me some hot coffee with which to refresh me spirit (=to refresh me spirit with). 他给我提供了点热咖啡提提神。

Nobel began to seek ways in which to make the explosive safer to handle.诺贝尔开始寻找那种炸药操作起来更安全的方法。

(六)作状语。不定式短语作状语，表示目的、原因、结果等。位置一般在句尾或句首。

(1)表示目的。如:

We waved flags, beat drums and blew bugles to encourage the players. 我们摇旗擂鼓吹号，来鼓励运动员。

They went to the U.S.A. not to study English but to study law and business. 他们去了美国，不是为了学英语，而是为了学法律和商务。

为了强调，有时用 in order to (为了)或 so as to (以便)加动词原形，放在句首或句尾均可。例如;

In order to improve my English, I read China Daily every day. 为了提高英语水平，我每天都看《中国日报》。

He took a taxi so as not to miss the train. 为了不误火车，他坐了出租车。

有些不定式习惯用语放在句首或句尾，作独立成分。例如：

To be frank(with you), this is not satisfactory. 老实(和你)说，这不令人满意。

To be fair, she is an honest girl. 说句公道话，她是一个诚实的姑娘。

To tell you the truth, you are wrong.. 实话告诉你，你错了。

这样的短语还有 to tell you the truth 实话告诉你，to conclude 最后， to begin with 首先，to cut a long story short 简而言之，to go back to the point回到正题，not to make too much of it 别小题大做，to put it another way 换句话说，to hear him talk听他说话的口气，等等。

(2)表示原因。例如:

To hear him talk in that manner, you would think him a foreigner. 他这样说话，你会以为他是外国人。The old father smiled to know his success. 知道他成功的消息，那位老父亲笑了。

不定式短语可以和表示情绪的形容词和过去分词连用，有时说明产生这种情绪的原因，有时不是说明原因，而是和形容词一起说明主语的情况。

常见的这类形容词和过去分词有：

able 有能力的，afraid 害怕的，amazed 感到惊异的，angry生气的，anxious 急于的，astonished 感到惊讶的， careful 小心的， certain 有把握的，clever聪明的， comfortable 舒服的，cruel 残忍的，deep 深的，delighted 高兴的， difficult有困难的， disappointed 感到失望的，determined 有决心的，eager 急于的， easy容易的，fit 合适的，foolish 愚蠢的，fortunate 幸运的， free 自由的，frightened 感到害怕的，glad 高兴的，good 好的， happy幸福的，hard 艰苦的，lucky 幸运的，overjoyed 高兴的， pleased 高兴的，possible 可能的，proud 自豪的，ready 准备好的，relieved 感到轻松的，right 正确的，sad 悲伤的，shocked 感到惊讶的，sorry难过的，sure 肯定的， surprised 感到惊讶的， unable 没能力的，useless没用的，willing 愿意的，worthy 值得的，wrong 错误的等。

例如：

He’ll be angry to hear these words. 听到这些话他会生气的。

You’re lucky to have me as your teacher. 有我当你们老师，你们很幸运。

He feels proud to be on the school football team. 作为校足球队队员他感到很自豪。

Be careful not to catch cold. 小心别感冒。

He’s anxious to go back straight to London. 他急于直接回伦敦。

They’ll be ready to leave in about an hour. 再有大约一小时他们就准备好了。

The new manager is easy to get along with . 新经理很容易相处。

This river is broad, deep and good tom in. 这条河宽且深，是游泳的好地方。

Your sofa is comfortable to sit in. 你的沙发坐上去很舒服。

(3)不定式做结果状语只限于下面几个词：learn 得知，find 发现，see 看见，hear 听见， to be told 被告知，make 使得 等。only+不定式常表示出乎意料的结果。例如:

He hurried to the airport to learn that the flight had already taken off. 他急忙赶到机场，却得知飞机已经起飞了。

He returned home from his holiday only to find that his house had been broken into. 他休假回家，却发现他的房子被破门而入了。

(4) 不定式还可以与“be said, be reported,…”等连用构成复合谓语。这一结构可变成“It’s said, It’s reported,…”(见被动语态部分)。如：

An explosion is reported to have happened, and three are known to have been killed.

= It’s reported that an explosion has happened and it’s known that three have been killed.

据报道发生了一起爆炸，已知三人被炸死。

(七)不定式的时态。动词不定式一般有三种时态形式，即一般式、进行式和完成式。

(1) 一般式(to+动词原形)：表示与主句谓语动词动作同时(或几乎同时)发生或在主句谓语动词之后发生的事情。例如：

We’re happy to have you on our side. 有你在我们这边我们很高兴。

I saw him go out. 我看见他出去了。( 不定式 go out 与 see同时发生。)

They invited me to have dinner with them. 他们邀请我和他们一起吃晚饭。

I hope to see you again. 我希望再见到你(to see 发生在 hope 之后)

(2) 进行式(to be+现在分词)：表示主句谓语的动作发生时，不定式动作正在进行。例如：

She’s said /believed to be living nearby. 据说/据信她就住在附近。

When he came in, I happened to be sleeping in bed. 他进来时，我碰巧正在床上睡觉。

They seem/appear to be enjoying themselves. 看上去他们似乎很快活。

He pretended to be doing his homework when he heard his father’s sound. 他听见父亲的声音，假装正在做作业。

The president was reported to be visiting the hospital. 据报道总统正在访问那家医院。

(3)完成式(to have+过去分词)：表示在主句谓语的动作之前发生的事情。

如：I’m glad to have met your parents here. 我很高兴在这儿见到了你父母。(已见过)

I’m sorry to have kept him waiting for me so long. 我很抱歉让他等了我这样久。(已经等过了)(八)不定式的被动语态。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形式。不定式的被动形式有两种：

一般式：to be+过去分词

完成式：to have been+过去分词

例如：

You’re lucky to have been accepted . 你很幸运已经被接受了。

These criminals are to be hanged . 这些罪犯是将被绞死的。

We’re glad to have been invited. 受到邀请我们很高兴。

What’s to be done next? 下一步做什么?

It is an honor for me to be asked to speak here. 我很荣幸应邀在这里讲话。

(八)为了避免重复，不定式可省略，但 to 有时保留，有时不保留。

例如：

You will make it if you try (to). 如果你努力，你会成功的。

George says he is going to leave Shanghai, but I don’t think he really wants to. George 说要离开上海，但是我不认为他真的愿意走。

Some of them retired, and others were ready to. 一些人退休了，还有的准备退。

He always speaks faster than he needs to. 他说话总是没必要的快。

I’d like to do it now, but I haven’t got the time (to). 我倒是想现在干，但没时间。

“Would you go there with me?” “I’m glad to.” “你愿意和我一起去吗?”“愿意。”

“Did you pass the exam?” “No, I tried (to), but I failed.” “你考试及格了吗?”“没有，我努力了，但没成功。

“Do you want to sing them an English song?” “I prefer not to.” “你愿意为他们唱首英文歌吗?”“我不想唱。”

You’d better sing an English song if they ask you (to) again.如果他们再要求你，你最后唱一首英文歌。

后面常省略不定式而保留 to 的结构，还有：

used to 常常 be going to 打算

mean to 打算 ought to 应该

plan to 计划 want to 要想

(九)两个不定式由 and, or, except, but, than 连接时，第二个可省略 to，尤其是两个不定式紧密相连时。

例如:

I intend to call on him and discuss this question again. 我打算去拜访他并和他谈谈这个问题。

I’d like to lie down and go to sleep. 我想躺下睡觉。

You’re free to talk or laugh here. 在这里你可以随便说笑。

I’m anxious to go and ask him about it. 我急于去问问他这个事。

Do you want to have lunch now or wait till later? 你想现在吃午饭还是再等会儿?

We had nothing to do except (to) look at the posters outside the cinema. 我们无事可做，只有看看电影院外面的招贴。

He had nothing to do except talk nonsense. 除了胡说八道，他没别的事干。

I would rather die than be insulted. 我宁死也不受侮辱。