1、非谓语动词常考易混点1. 不定式和动名词作主语（1） 一般情况下可以互换使用，意义无很大区别。（2） 在实际使用中，选择不定式还是动名词作主语，主要依据以下原则： 不定式作主语一般表示特定的、具体的动作，也往往用形式主语 It is to do sth 的形式表达；而动名词作主语则表示抽象的、泛指的动作，只有 It is +否定意义的形容词或名词(no use, no good)的句型中用形式主语。It is a pleasure to help others. 帮助别人是一件乐事。It is no good doing nothing all day long. 整天无所事事不好。Your
2、saying that is useless. 你那么说没有任何用处。To eat too much sugar is bad for your health. 多吃糖对身体有害。 一般来说，用动名词的复合结构作主语，不用不定式的复合结构作主语。（正）Your saying that is useful.在主系表结构中，主语和表语所采用的非谓语形式要一致。To see is to believe. 眼见为实。Teaching is learning. 教学相长。To waste time is to waste life. 浪费时间就是在浪费生命。2. 动名词和不定式作表语动名词作表语表示一般
3、情况，一般可以和主语互换位置，意义不变；不定式作表语往往表示将要发生的事。Her job is washing clothes. 她的工作是洗衣服。上句还可表示为 Washing clothes is her job.His wish is to become an artist. 他的愿望是成为一名艺术家。 （表将来）3. 不定式可以做目的状语、原因状语和结果状语（1）目的状语To do first aid correctly, you have to study with a teacher.In order not to waste electricity, we turned the
4、light off.Check your composition carefully so as to avoid mistakes. (so as to 只能置于主句之后)（2）原因状语The two friends were pleased to see each other again.Nice to meet you again.（3）结果状语表示主语未曾预料到的结果，尤其是指不愉快的结果。有时不定式前可用 only.They lifted a rock only to drop it on their own feet. 搬起石头，砸自己的脚。He worked hard only
5、to fail. 他很努力，但结果还是失败了。I woke early to find it was snowing. 我早早醒来，看到在下雪。动名词作结果状语表示自然而然的结果。4. tooto句型并非都表示否定含义（1）一般情况下，此结构表示“太以致不能”这一否定结构。You are too young to go to school. 你年纪太小了，不能上学。The question is too difficult to answer.这个问题太难了，无法回答。（2）当 too 前出现 only, but, all 等副词时，tooto句型不再表示否定的意义，only(but, all
6、) too相当于 really，too 没有否定的含义，相当于 very.I am only too glad to receive your nice gift. 我非常高兴地受到你的精美礼物。We are but too eager to hear from you. 我们及其渴望受到你的来信。(3)当句型中的形容词是表示“难” “易”或表示某种心情的形容词，如 ready, easy, glad, pleased 等时，too 作“十分，极其”解，表示肯定的意义。She is too ready to help others. 她很乐于助人。His mother is too easy
7、to get angry. 他母亲太容易发脾气了。（4）never(not)+tooto句型为“不会太所以能” 之意。否定词 never(not)与含否定意义的tooto句型一起构成双重否定，即为肯定含义。One is never too old to learn. 活到老，学到老。It is never too late to mend. 亡羊补牢，未为晚也。She did not get up too late to catch the early bus. 她起得早，赶上了早班车。(5)toonot to句型表示肯定含义，意义为“太不会不” 。He is too kind not to
8、help you. 他这么好，不会不帮助你的。5.关于 to have done(不定式的完成式 )（1）不定时的完成式与表示愿望的动词如 expect, intend, wish, plan, want, mean, suppose 的过去时以及 would like/love 等连用，表示过去未曾实现的愿望。I meant to have given you the dictionary yesterday, but I forgot to bring it here.我本想昨天把字典给你，但我忘记带来了。He intended to have written the manager a
9、letter this morning, but he was too busy.他本想今天上午给经理写封信，但他太忙了。（2）不定式的完成式可用来表示不定式动作发生在句子的谓语动词之前。Im sorry to have taken up so much of your time. 很抱歉我占了你如此多的时间。She is said to have learned several languages. 据说她已经学了几种语言。(3)不定式的完成式与 expect, hope 等的现在时连用，表示预计将要完成的动作。We expected to have finished the task by
10、 the end of next month.我们预计下月底会完成任务。Were leaving at 8, and hoped to have reached there by sunset.我们将于八点出发，希望到日落时到达。6.动词不定式中原形动词的省略与不定式符号 to 的省略(1)在使役动词 let, have, make 和感官动词 feel, see, watch, notice, observe, listen to, hear 后作宾语补足语，不定式的符号 to 要省略。Mr Wang has his son write a diary every day. 王先生让儿子每天
11、写一篇日记。I knew him very much because I had seen him grow up from childhood. 我很了解他，因为我是看他从小长大的。注意：将上述句子变为被动句，即不定式由宾补变成了主补，这时不省略 to.（2）介词 but 或 except 之后跟不定式作宾语，且 but 或 except 前面是实意动词 do 的任何一种形式时，不定式符号 to 要省略.There was nothing I could do but wait. She would do anything except clean the floor.（3）两个或两个以上功
12、能相同的不定式并列使用时，第一个 to 要加上，之后的不定式符号 to 要省略.The teacher asked us to bring some food, wear more clothes and get there on time.To make him happy and encourage him to work harder, I gave him a walkman as a gift.（4）为了避免重复，在 hope, wish, want, like, love, decide, plan, need, mean, forget, refuse, tell, know,
13、haveto, be going to, used to, ought to 等动词后面再次出现相同的不定式作宾语时，常出现单独使用的to，而把曾出现过的动词省略掉。Mrs King lied to us because she had to. 金女士跟我们撒了谎，因为她不得不这样做。-Would you like to go skating with us? 和我们去滑冰好吗？-Id like /love to, but I have a lot of homework to do. 我想去，但我有许多作业要做。-I heard that you would go to Dalian for
14、 your holiday. 听说你要到大连去度假？-I planned to, but I have some important business to deal with. 原计划去的，但我有重要的事要处理。（5）不定式在 afraid, anxious, able, eager, glad, lucky, sorry, willing 等形容词后面出现且有上下文时，常出现单独使用的 to，而把曾出现过的动词省略掉。-Ill be away on a business trip. Would you mind looking after my cat?-Not at all. Id be
15、 glad to.行，非常乐意。（6）在 ask, tell, expect, force, invite, beg 后面做宾补时，常出现单独使用的 to，而把曾出现的动词省略掉，以免重复。John didnt pass his driving test, but I expected him to.Jane came to my birthday party last night, but I didnt invite her to.(7)但是，如果在省略的不定式结构中含有 be, have, have been 时，要保留这些词。-Hasnt he finished writing the
16、 report?-No, but he ought to have.-Arent you the headmaster?-No, and I dont want to be.China is no longer what it used to be.7.不定式的主动和被动（1）不定式修饰的名词或代词和不定式逻辑上构成主谓关系时，不定式往往用主动形式。Do you have a knife to cut the watermelon?(2)不定式和它前面被修饰的名词或代词构成逻辑上的动宾关系，又和该句主语构成逻辑上的主谓关系时，不定式常用主动形式。She has a sister to look
17、 after.（3）在形容词+不定式结构作表语，宾补和定语时，其中形容词多为表示性质的词，如：easy, hard, difficult, interesting etc.These apples are good to eat.I find the lecture difficult to understand.He is a man easy to get on with.(4)tooto结构中The passage is too hard to translate.（5）在疑问代词+不定式结构中I dont know what to do next.She will tell you w
18、hich bus to take. Do you know who to go with?（6）在不定式作定语，与被修饰词之间有动宾关系，而与句中的另一名词或代词之间有主谓关系时I have a meeting to attend today.Do you have anything to say?但如果没有这种主谓关系，则不需要用不定式的被动形式Im going to Beijing next week. Do you have anything to be taken to your parents?（7）在下列句型中，to let, to blame, to seek 等用主动形式表被动
19、含义。The house is to let.Who is to blame for it?The reason is not far to seek. 理由不难找到。（8）在 there be 结构中，用来修饰主语的不定式可以用主动形式，也可以用被动形式。There is no time to lose. There is no time to be lost.若不定式前加 for sb 做逻辑主语时，不定式用主动还是被动取决于 sb 是动作的执行者还是承受者。There are many problems for us to deal with.There are many reasons
20、 for the books to be published.Exercises:1. The pilot asked all the passengers on board to remain _ as the plane was making a landing.A. seat B. seating C. seated D. to be seating2. Dont leave the water _ while you brush your teeth.A. run B. running C. being run D. to run解题思路：leave 后接宾语及宾补时，有 “留下，使处
21、于某种状态”之意。构成以下结构：leave sb/sth doing sthleave sth undoneleave sb to do sthleave sth to be done本题符合结构3. The old man, _ abroad for twenty years, is on the way back to his motherland.A. to work B. working C. to have worked D. having worked4. I send you 100 dollars today, the rest _ in a year.A. follows B
22、. followed C. to follow D. being followed解题思路：此题考查独立主格用法。逻辑主语 the rest 与 follow 之间的关系为逻辑上的主动关系。而 A 项 follows 为谓语动词，题干句逗号后没有连词不能跟句子。句中的 in a year 暗示将来，所以用不定式表将来，与 the rest 构成独立主格结构。5. oil prices have risen by 32 percent since the start of the year, _ a record US 57.65 a barrel on April 4.A. have reached B. reaching C. to reach D. to be reachingreaching 做结果状语
