非谓语动词（不定式的用法小结）非谓语动词（不定式的用法小结）动词不定式用法小结动词不定式是一种非谓语动词形式，其结构为“ to do ”，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。
但有时态和语态的变化。
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,独立成分或与疑问词等连用。
一、结构： to do 否定式：not to do二、时态和语态不定式主动语态被动语态一般式to do to be done进行式 to be doing------------完成式to have done to have been done完成进行式to have been doing-----------(1).They pretended not to see us. (一般式表示与谓语的动作同时/几乎/发生在它之后.)(2). He pretended to be sleeping. (在谓语动词发生的同时,不定式的动作也正在进行)(3).She pretended to have known it before.(完成式表示动作发生在谓语动作之前)(4).We’re happy to have been working with you.(完成进行式表示谓语动作发生之前,不定式的动作一直在进行而且可能之后也继续)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。
☆单个不定式作主语时,谓语动词用单数☆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：1) To learn English well is not easy.= It is not easy to learn English well.2) To use English every day is important for students. = It is important for students to use English every day.二. 作表语：( 系动词+ to do sth. ) 动词不定式（短语）作表语常用于系词be的后面。
例：1) 他的工作是开车。
His work is to drive a car.2) 我的工作是饲养动物。
My job is to feed animals.3) 她的理想是当医生。
Her ambition is to be a doctor.三. 作宾语 ( vt. + to do ) 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 , decide, expect, want, hope, wish, offer, fail, plan, learn, pretend, refuse, manage, help, agree, promise, prefer, mean 等等例如：1）I want to tell you a story. 我想给你讲个故事。
2）They begin to work at eight every morning. 他们每天早晨8点开始工作。
3）Don’t forget to lock the door.别忘了锁门。
4）Would you like to go and have a picnic with us tomorrow? 明天和我们一起去野餐好吗？☆注意： *如果and连接两个动词不定式，第二个动词不定式一般省“to”例：（1）He wants to go and have a swim with us. 他想和我们一起去游泳。
（2）若作宾语的动词不定式（短语）很长，可用it作形式宾语。
☆ I find it interesting to learn English with you. 我觉得和你一起学英语很有趣。
☆ He found it hard to catch up with others. 他觉得赶上别人很困难。
四. 作宾语补足语。
可以用动词不定式作宾语补足语的动词有：(want, wish, ask, tell, order, beg, permit, help, advise, persuade, allow, prepare, cause, force, call on, wait for, invite 等等：1. ( vt. + 宾语 + (to) do sth. ) 例如：The teacher asked us to read English for half an hour in the morning. 老师让我们早晨读半小时英语。
Please let me help you. 让我来帮助你。
2. with+宾语+ to do (表示将来的动作)With a lot of work to do, he didn’t go to the cinema. 对比：With all the work done, he went to the cinema.☆不定式作宾语补足语可以归纳为以下三种句式：1.要带to 的不定式作宾语补足语：tell /ask / want / would like / wish / like / invite /encourage /teach sb. to do sth.例：The teacher told us to come earlier tomorrow.I want you to go now. 我想让你现在就走。
Her parents wish her to be a teacher. 她父母亲希望她当老师。
2.不带“to”的不定式作宾语补足语：Let / make / have / see / watch / hear / notice / feel sb. do sth.Let the boy go out now. 让那个男孩出去。
The boy made the baby cry. 男孩弄哭了这个小孩。
I saw the students play basketball on the playground yesterday. 昨天我看见学生们在操场打篮球。
3.可省可不省的： help sb. （to）do sth.I often help my mother（to）do housework. 我经常帮妈妈做家务。
☆注意：如果将主动语态变为被动语态时，作宾语补足语的动词不定式变为主语补足语，动词不定式则不省“to”，即原来省的再加上，例：The boy made the baby cry. = The baby was made to cry by the boy. 那个孩子被男孩弄哭了。
4. ☆特别注意☆：不定式用在介词but, except, besides后时,如果这些介词前有行为动词do，does, doing, did, done,那么介词后的不定式不带to, 如果没有则要带to. (有do无to，有 to无 do．)(1). She could do nothing but cry.(2). What do you like to do besides sleep.(3). I have no choice but to go.五. 动词不定式作定语动词不定式作定语常用来修饰名词或不定代词，放于所修饰的词后，为后置定语，与所修饰的词有如下关系：1. 动宾关系：I have a meeting to attend.2. 主谓关系（be the first/second/last… to do ）：He is always the first one to come.第一个到太空的中国人是杨利伟。
The first Chinese to travel in space was Yan Liwei.3. 同位关系(说明所修饰名词的内容)：We all have a chance to go to college.☆ 注意：不定式为不及物动词时，所修饰的名词如果是地点、工具等，要有相应的介词，如：He found a good house to live in. 他找到了一幢很好的房子住。
Please give me a pen to write with. 请给我一支写字的笔。
☆但如果不定式修饰的是 time, place, way等就可以省略介词：如：He has no place to live.4. something, anything, nothing, everything 等复合不定代词常用不定式作后置定语Do you have anything to send.六. 动词不定式作状语：1. 作目的状语，常用在go, come, hurry等不及物动词后，表目的。
（常用的短语：in order to do, so as to do 等等：例如：He came here to see you.In order to keep healthy, he often play sports.2. 作结果状语：（常用结构：too…to; so …as to do; …enough to do; only to do; never to do.）1) I visited him only to find him out.2) Mike ate so much as to have a stomachache that day.☆ 注意：too…to 是否定的，表示太…而不能…, 但是，当too前面有only, all, but 时，意思是非常… 相当于very,是肯定的。
例如： I am only too pleased to be able to help you 能帮助你我非常高兴。
3. 作原因状语：（sb. + be/ feel +adj/adv + to do. ）例如： They are very sad to hear the bad news.4. 表示程度 The question is easy for him to answer.七. 不定式和疑问词连用，可以作句子的主语、宾语、表语等。