动词不定式用法讲解.docx

1、动词不定式用法讲解动词不定式用法讲解1、构成与特征动词不定式(infinitive)是动词的一种非限定形式，即非谓语动词形式，它有两种形式：一种是“to + 动词原形构成to- infinitive；另一种是不带to的不定式,即动词原形(bare- infinitive)。所有行为动词都有不定式形式，其否认式是在不定式前加not。动词不定式或不定式短语没有人称和数的变化，在句子中不能作谓语。动词不定式仍保存有动词的特点：1可以有时式和语态的变化，也可以有自己的宾语或状语，它们一起构成了不定式短语。He tried to work out the problem in five minutes.

2、他试图在五分钟之算出这道题。带宾语和状语The factory to be built here next year is a car factory.明年在这里建的工厂是一家汽车制造厂。有语态的变化2动词不定式还具有名词、形容词和副词的特征，在句中可以作主语、宾语、表语、补语、定语、状语等成分。He wants to study English.他想学英语。to study English在句中作want的宾语，而to study又有自己的宾语English, to study和English一起构成了不定式短语。Never to offend anyone is his principle

3、.不得罪人是他的原那么。不定式作主语注意：不定式在许多场合具有情态意义。作主语时，相当于一个带有情态动词的主语从句；作宾语时，相当于一个带有情态动词的宾语从句；作定语时，相当于一个带有情态动词的定语从句；作目的状语时，相当于so that 或in order that引导的目的状语从句。It is right for her to say so.(= It is right that she should say so.)她这样说是对的。He has a lot of work to do.(= that he should do)他有很多工作要做。I dont know where to g

4、et the ticket.(= where I could get the ticket.)我不知道哪里能买到票。She opened the door for the children to come in.(= so that the children might come in)她打开门目的是让孩子进来。2、动词不定式的时态和语态动词不定式有一般式、进展式、完成式、完成进展式四种时态变化形式，一般式和完成式有被动语态变化形式。主动语态 被动语态一般式 to write to be written进展式 to be writing完成式 to have written to have b

5、een written完成进展式 to have been writing1不定式的时态意义不定式的时态是以句中谓语动词的时间为依据的。不定式的一般式不定式的一般式表示的动作或状态通常发生在谓语动词之后或同时发生。They made plans to live in Paris.他们计划住在巴黎。to live 发生在 made plans之后I heard them talk in whispers all the time at the meeting.我听见他们会议期间一直小声说话。不定式talk与谓语动词heard同时发生不定式的进展式不定式的进展式表示其动作正在进展，与谓语动词发生的

6、动作同时进展。He pretended to be listening to me carefully.他假装认真地听我讲。When he came in ,I happened to be reading the novel.他进来时，我碰巧正在读小说。注意：不定式的进展式常同may, might, can, could, must, need, ought to, should, will, would 等情态动词连用，表示“可能、应当或想必正在进展的动作。You oughtnt to be talking so much. 你不应该说这么多。He might be reading a n

7、ovel at that time. 那时他可能正在读小说。It is good to sit here with you.(坐下来时讲这句话)It is good to be sitting here with you.(一坐在座位上时讲这句话)He is said to write a preface to the book.(表示将来)He is said to be writing a preface to the book.表示进展不定式的完成式不定式的完成时表达以下意义：a. 不定式的完成式所表示的动作或状态发生在谓语动词所表示的动作之前。I am sorry to have ke

8、pt you waiting.对不起，让你久等了。to have kept发生在I am sorry所表示的时间之前She is said to have just completed a novel.据说她刚完成一部小说。to have just completed a novel发生在She is said所表示的时间之前b. 用在intended, expected, meant, hoped, promised, planned, wished, thought, desired, was, were等词后，不定式的完成式表示未曾实现的愿望、期待、想法、打算或计划等。to have +

9、 过去分词表示动作， to have been表示状态。I meant to have done the work before Sunday.我本想星期天前完成这项工作。没完成I was to have been a doctor.我本打算当个医生。没当成I intended to have come to see you.我本打算来看你的。(但没来)C .用在seem, appear, thing, consider, believe等后，表示一个动作先于另一个动作发生。I seem to have seen her somewhere before.以前我好似在那见过她。see在seem

10、之前发生He was believed to have been a reporter.都认为他从前干过记者。比拟：She seems to have been ill.= It seems that she has been ill.她似乎病了。She seemed to have been ill.= It seemed that she had been ill.她似乎过去生过病。d. 在should(would) like 或should(would)have like后用不定式完成式表示没有实现的愿望。I should like to have gone with her.我多么愿意

11、和她一起去。但没去I would like to have seen her face when she read the letter.我真想见到她读信时的表情。但没看到不定式的完成进展式表示动作在谓语动词之前发生，而且一直进展着。He was happy to have been staying with his uncle.他很高兴一直跟他叔叔住在一起。He looked too young to have been publishing books for six years.他看上去很年轻，不像已经出版了6年书的人。 come + 不定式表示一个动作发生的过程He will come

12、 to understand it in the end.他最终会懂得的。Later he came to be a famous painter.后来他成了著名的画家。2动词不定式的被动语态如果不定式的逻辑主语是不定式动作的执行者不定式用主动式；如果不定式的逻辑主语是不定式动作的承受者时，不定式用被动语态。The doctor recommended him to air the room.医生建议他让房间透透气。主动式The doctor recommended the room to be aired. 医生建议让房间透透气。被动式The sports meeting on the we

13、ekend has to be put off.周末的运动会被迫推迟。被动式What is to be done next?下一步干什么？被动式3意义上被动形式上主动的不定式 在“there be+主语中，不定式用作定语修饰名词或代词，并同所修饰的名词或代词是逻辑上的动宾关系。There is no time to lose.一点时间也不能浪费了。There are a lot of clothes to wash.有许多衣服要洗。There is nothing to do at the moment. 暂时无事可做。在“名词代词 be easy(difficult, fit等形容词) 不定

14、式结构中，有时尽管主语是动作的承受者，不定式在意义上是被动，形式上却是主动，这时可以看成省略了动词逻辑主语for us, for me , for you 等。The book is difficult to read. 这本书很难读懂。He is not easy to get on well with. 他不易相处。如果不定式逻辑主语是不定式动作的执行者，不定式和它修饰的名词虽然在逻辑上有动宾关系，也必须用主动形式，因为逻辑主语同不定式的关系更为直接。Weve got plenty to eat.我们有足够的东西吃。句子主语We在逻辑上是不定式to eat动作的执行者，不定式to eat和

15、它修饰的名词plenty在逻辑上是动宾关系，用主动形式表示被动意义。Most people have some similar experience to remember. 大多数人都有一些相似的体会值得记忆。句子主语Most people在逻辑上是不定式to remember动作的执行者，不定式to remember和它修饰的名词experience在逻辑上是动宾关系，用主动形式表示被动意义。注意：不定式和句中主语或其它成分如果不是逻辑上的主谓关系，不定式仍宜用被动形式。He described the black slaves to be sold at auction.他描写了那些被拍

16、卖出售的黑人奴隶。We thought the meeting to be held very important.我们认为即将举行的会议很重要。在too to 和enough to 结构中，不定式可用主动语态表示被动意义。The box is too heavy to carry.这个箱子太重了搬不动。The book cheap enough to buy.这本书很廉价可以买。blame的不定式作表语时，用主动语态和被动语态表示被动的意义，但含义不同。You were to blame. = you are at fault.这该怪你。You were to be blamed.(= Yo

17、u are going to be blamed.)你要受到指责。something, little, what, much, a great deal等作句子主语，表语为to do时，不定式可用主动语态表示被动意义。A great deal of work remains to do.还有很多工作要做。What is to do tomorrow? 明天干什么？to let 表示“出租作表语时，可用to be let形式，但含义上有些差异。This house is to let. 此房出租。从房屋主人的立场讲话，由于房子主人亲自向租房人说或登出广告This house is to be l

18、et. 此房出租。(从房屋本身来说，代理人向租房人讲话)a. 不定式和它所修饰的词必须是逻辑上的动宾关系，如果是逻辑上的主谓关系，意义不是被动而是主动。They have the ability to change things for the better.他们具有使事态好转的能力。Its a picture to guide you.这是衣服可以指引你的图。b. 在同一场合，某些不定式可用主动形式或被动形式，但含义常有细微差异。主动形式经常带有一定的情态意义，如可能、必要、应该等，而被动形式那么不带情态意义。例如：There is nothing to see. 没有什么值得看的。指没有东

19、西可看There is nothing to be seen. 什么也看不见，指没有东西被看见c. 如果不定式与其逻辑主语或被修饰的名词之间存在逻辑上的动宾关系，而不定式中的动词是不与物动词或虽是与物动词，而其本身已经带有宾语的，那么不定式后应加一个适宜的介词。I have no paper to write on.我没纸写字。I need a chair to sit on.他需要一把椅子坐下。d. 以下句型必须用被动式Theres still much left to be described.还剩很多要描述。There is no sound to be heard.没听见声音。3、动词

20、不定式的句法功能动词不定式具有名词、形容词和副词的特征，因此在句中可以作主语、表语、宾语补足语、定语和状语。1不定式作主语To make a plan first is a good idea.先制订计划是个好方法。To die for our motherland is a great honour.为祖国而死，死得光荣。不定式与不定式短语作主语时，为了平衡句子结构，可用it作形式主语，而把真正的不定式后置。It is a good idea to make a plan first .首先制订一个计划是一个好主意。Its a great pleasure to see you again.

21、再次见到你太好了。Its bad manners to stare at a foreign guest.盯着外国人看是不礼貌的。在以下情况下只宜采用it作形式主语a. 在疑问句或感叹句中作主语的不定式。Isnt it a good idea to set up a lab of our own?建一座我们自己的实验室不是个好主意吗？How important it is to master a foreign language!掌握一门外语是多么重要啊!b. 当句中谓语动词不是be, seem, appear等连系动词时。It took us 20 minutes to get to the

22、 station.赶到车站花了我们20分钟。It made the boy greatly pleased to get the gift.得到礼物使男孩大为高兴。c. 在“it +be + adj.+ of + sb.+不定式结构中。Its very nice of you to help me with my work.帮我的工作，你真是太好了。It was silly of us to do so.我们这样做真是太傻了。d. 有时候，作主语的不定式相当于一个条件从句。To love others is to be loved. If you love others you will be

23、 loved by others.爱人即爱己。To build an expressway across the country requires a lot of money.= If you build an expressway across the country, it will require a lot of money.建一条贯穿全国的高速公路需要很多钱。e.如果作主语的不定式短语是与物动词宾语，那么可以把宾语转换为主语，而不定式移到句尾。To revise the poem took her two weeks. = The poem took her two weeks t

24、o revise.修改这首诗花了她两周的时间。the poem 是revise的逻辑宾语To talk with Helen is interesting.= Helen is interesting to talk with.同海伦谈话很有趣。2不定式作表语主语、表语都是不定式，前者是条件，后者是目的或结果。To learn a language is to use it.学语言是为了使用语言。To be kind to the enemy is to be cruel to the people.对敌人仁慈就是对人民残酷。主语是duty, plan, wish, hope, idea, p

25、urpose等名词。His wish was to become a scientist.他的愿望是当一名科学家。To the doctor ,the most important thing is to save peoples lives.对医生来说，最重要的事是拯救人们的生命。表示时态开展的结果、预期的结果、不幸的命运或预言。You are to die at 98.你会98岁去世。Man is to live a better life in the next century.人类在下一世纪会生活的更好。表示“同意、安排、命令、决定、劝告、意愿 、禁止等。They are to mar

26、ry next week.安排他们下周结婚。Nobody is to know.禁止不应让任何人知道。You must be patient and persistent if you are to succeed.愿望要想成功，就必须有耐力，有毅力。主语是what引导的名词性从句。What surprised me most is to see him beaten black and blue.使我吃惊的是看到他被打得遍体鳞伤。What is important at present is to save lives.目前救人要紧。3不定式作宾语有些与物动词常跟不定式作宾语，如agree,

27、 afford, arrange, ask, begin , decide, forget, hope, like , start , want, wish等。She wanted to borrow my bike.她想借我的自行车。They began to read and write.他们开始读写。不定式也可用来作形容词的宾语，如able, afraid, anxious, careful, content, determined, eager, foolish, free, glad, inclined, likely, pleased, prepared, ready, slow,

28、 sure, sorry, willing等。The boys and girls are anxious to learn how to swim.孩子们渴望学会游泳。Im glad to meet you.见到你我很高兴。a. 不定式作宾语时，句子的主语是不定式的逻辑主语，与不定式动词的关系是主动关系，但有时不定式和主语却是动宾关系。English is not difficult to learn.英语不难学。The question is easy to answer.这个问题很好回答。b. feel, find, judge, make, think, believe, consid

29、er等动词后如果是不定式作宾语，后面有宾语补足语时，将真正的宾语不定式放在补足语的后面，而将形式宾语it放在补语之前。He found it hard to learn maths.他发现数学很难学。I think it our duty to support the elder.我认为赡养老人是我们的义务。4不定式作定语不定式作定语时，需放在它所修饰的名词或代词之后。它与所修饰的名词或代词有以下关系：动宾关系Have you got anything to say?你有什么要说的吗？She did not have much money to spend.她没有更多的钱花。注意：如果不定式的

30、动词是不与物动词，和所修饰名词搭配的介词不能省略。He had no room to live in.他没房子住。There are 60 desks for us to sit by.有六十桌子供我们坐。主谓关系He is always the first to come and last to leave.他总是第一个来，最后一个走。The next train to arrive is from Washington.下一列到站的火车是从华盛顿开来的。同位语关系The farmers thought of ways to protect their crops.农民们想出保护庄稼的方法。

31、He had the wish to be an artist. 他愿意当艺术家。a. 不定式可以修饰there be 结构中作主语的名词There is nothing to worry about.没什么可担心的。There is enough money to spare.钱足够用。b. 有些动词和形容词后常跟不定式，这些词派生出来的名词ability, agreement, anxiety, attempt, claim, decision, determination, eagerness, need, plan, promise, tendency, willingness, wish, impatience, inclination等常跟不定式作定语,这类词后的不定式常表同位关系She had a tendency to talk too much.她喜欢唠叨。His eagerness to get back home was quite obvious.看的出，他急于回家。5不定式作状语不定式作状语时，常表示目的、结果、原因、条件等，通常放在它所修饰的动词之后。表目的不定式作目的状语时，其动