# 不定式用法讲解

（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 一般式 完成式 进行式 完成进行式 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.
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to do to have done to be doing to have been doing

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.
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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
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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。

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－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。
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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。
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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

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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 31. He was too excited _________. A. speak B. to speak C. not to speak

C. of thinking

D. speaking
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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

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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

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[参考答案] 1-5 DBBAA 21-25 ACCAB 41-45 DDCDB 6-10 CCAAA 26-30 DACBA 46-50 CCDDBA 11-15 CADAB 31-35 BCCCB 16-20 BBAAA 36-40 BBDAB

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___ 动词不定式用法归纳 动词不定式没有人称和数的变化,在句中不能独立作谓语。