动词不定式要点总结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、宾语补足语、定语和状语。一、常接不定式作宾语的动词有want，love，learn，agree，decide，hope，refuse等。例如：Im learning to skate on real ice. 我正在真正的冰上学滑冰。特别提醒不定式短语作宾语时，如果还带有宾语补足语，通常用it作形式宾语，而把不定式短语放在宾语补足语之后。例如：He found it very difficult to get to sleep.他发现入睡很困难。二、动词不定式常用作目的状语。例如：He came to give us a talk yesterday. 他昨天来给我们作了个报告。Mrs Brown went to see her doctor. 布朗夫人去看她的医生了。三、tell，ask，want，order，get，wish，warn，teach，invite等动词后常跟不定式作宾语的补足语，构成tell/ asksb to do sth（“告诉/请某人做某事”）结构。例如：Could you ask him to call me，please？ 请你让他给我打个电话，好吗？特别提醒使役动词let，make，have等，感官动词see，hear，feel，watch，notice，look at，listen to等，后常跟不带to的不定式作宾语补足语。例如：A woman saw it happen when she was walking past. 一位妇女路过时看到（它掉下）了。We often heard her sing in the next room. 我们经常听到她在隔壁唱歌。注意：在被动语态句子中，不定式前必须加to.例如：He was made to do it. 他被迫做这件事。She was often heard to sing in the next room. 经常听到她在隔壁唱歌。四、不定式短语作定语要放在被修饰的词语之后。例如：I have a lot of work to do. 我有许多事情要做。五、不定式短语作主语时，常用it作形式主语，真正的主语不定式短语放在后面。例如：It is right to give up smoking. 戒烟是有益的。六、作表语。例如：To him，the first important thing was to save lives. 对他来说，最重要的事情就是拯救生命。His wish is to become a scientist. 他的愿望是当一名科学家。七、动词不定式用在疑问词how，when，where，what，which等之后，作宾语或宾语补足语。例如：He taught us how to use a computer. 他教我们如何使用计算机。I dont know where to go？ 我不知道去哪里。1) 动词+ 不定式afford, aim, appear, agree, arrange, ask, be, decide, bother, care, choose, come, dare, demand, desire, determine, expect, elect, endeavor, hope, fail, happen, help, hesitate, learn, long, mean, manage, offer, ought, plan, prepare, pretend, promise, refuse, seem, tend, wait, wish, undertakeThe driver failed to see the other car in time.司机没能及时看见另一辆车。I happen to know the answer to your question.我碰巧知道你那道问题的答案。2) 动词+不定式；动词+宾语+不定式ask, beg, choose, expect, hate, help intend like, love, need prefer, prepare, promise, want, wishI like to keep everything tidy.我喜欢每件东西都保持整洁。I like you to keep everything tidy.我喜欢你使每件东西都保持整洁。I want to speak to Tom. 我想和汤姆谈话。I want you to speak to Tom. 我想让你和汤姆谈话。3) 动词+疑问词+ todecide, know, consider forget, learn, remember, show, understand, see, wonder, hear, find out, explain, tellPlease show us how to do that.请演示给我们如何去做。There are so many kinds of tape-recorders on sale that I cant make up my mind which to buy.有这么多的录音机，我都拿不定主意买哪一种。注意:疑问词带不定式在句中作成分时，谓语动词用单数。如：The question is how to put it into practice.问题是怎样把它付诸实施。2. 不定式作补语1) 动词+宾语+不定式(to do)advise, allow, appoint, believe, cause, challenge, command, compel, consider, declare, drive, enable, encourage, find, forbid, force, guess, hire, imagine, impel, induce, inform, instruct, invite, judge, know, like, order, permit, persuade, remind, report, request, require, select, send, state, suppose, tell, think, train, trust, understand, urge, warna.Father will not allow us to play on the street.父亲不让我们在街上玩耍。b.We believe him to be guilty. 我们相信他是有罪的。Find 的特殊用法Find后可用分词做宾补，或先加形式宾语，再加形容词，最后加带to的动词不定式。find后也可带一个从句。此类动词还有get，have。I found him lying on the ground.I found it important to learn.I found that to learn English is important.典型例题 The next morning she found the man _ in bed，dead.A. lying B. lie C. lay D. laying答案：A.find的宾语后面，用分词或分词短语，起宾语补足语作用。现在分词表达主动，也表达正在进行，过去分词表达被动。2) to + be 的不定式结构，作补语的动词。acknowledge, believe, consider, think, declare(声称), discover, fancy(设想), feel, find,guess, judge, imagine, know, prove, see(理解), show, suppose, take(以为), understandWe consider Tom to be one of the best students in our class.我们认为汤姆是班上最好的学生之一。典型例题Charles Babbage is generally considered_ the first computer.A. to inventB. inventing C. to have invented D. having invented答案：A. 由consider to do sth. 排除B、D。.此句只说明发明这一个事实，不定式后用原形即可。而C为现在完成时，发明为点动词一般不用完成时，且此处也不强调对现在的影响，因此不选C。3) to be +形容词seem, appear, be said, be supposed, be believed, be thought, be known, be reported, hope, wish, desire, want, plan, expect, meanThe book is believed to be uninteresting.人们认为这本书没什么意思。4) there be+不定式believe, expect, intend, like, love, mean, prefer, want, wish, undrstandWe didnt expect there to be so many people there.我们没料到会有那么多人在哪里。注意:有些动词需用as 短语做补语，如regard, think believe, take, consider.We regard Tom as our best teacher.我们认为汤姆是我们最好的老师。Mary took him as her father .玛丽把他当作自己的父亲。3. 不定式作主语1) Its easy (for me) to do that. 我做这事太容易了。easy, difficult, hard, important, possible, impossible, comfortable, necessary, better;the first, the next, the last, the best, too much, too little, not enoughIts so nice to hear your voice.听到你的声音真高兴。Its necessary for you to lock the car when you do not use it.当你不用车的时候，锁车是有必要的。2) Its very kind of you to help us.他帮助我们，他真好。kind, nice, stupid, rude, clever, foolish, thoughtful, thoughtless, brave, considerate(考虑周到的), silly, selfish(自私的)It was silly of us to believe him.我们真愚蠢，竟然相信了他。It seemed selfish of him not to give them anything.他不给他们任何东西，这显得太自私了