高中英语语法复习--动词不定式的用法

动词不定式专题复习动词不定式专题复习动词不定式的形式：动词不定式的形式：动词不定式的用法动词不定式的用法1.不定式作主语原则上，可用动词不定式直接作句子的主语，通常用 it 作句子的形式主语，而把不定式移到后面，形成 “It + 谓语 + 动词不定式”的句型。如：To catch the 5：00 bus early in the morning is not a good idea.It is not a good idea to catch the 5：00 bus early in the morning. To learn a foreign language well takes painstaking efforts. It takes painstaking efforts to learn a foreign language well. 若要说明不定式的动作的执行者，可以在不定式前面加上“for + 名词或代词”结构，或是“of + 名词 或代词”结构。It is a great pleasure for me to talk with him. It is very kind of you to help me . 可用于“of + 名词/代词 + 动词不定式”结构中作主语补足语的形容词是指那些可以表示人或事物的性 质或品质的好坏的形容词。这些词如：careful， cruel， foolish， bold， brave， good， honest， kind， rude， polite， nice，stupid， selfish， silly， wicked， wise， thoughtful， wrong 等。2.不定式作宾语不定式作宾语有两种情况：一是及物动词后直接跟带 to 的不定式，二是“动词+疑问词+带 to 的不定式”。“动词+带 to 的不定式”结构：常见的以不定式作宾语的动词有 afford， appear， agree， ask， believe， decide， demand， desire， fail， hope， intend，learn， mean， offer， promise，refuse， wish 等。如：I cant afford to buy a house. “动词+疑问代（副）词+不定式”结构：常见的这类动词有 advise， decide， forget， know， learn， remember， see， tell， think， teach， wonder，discover， understand， guess， explain 等。这类疑问代（副）词 what， when， which， where， how， whether 等（不包含 why）。如：She does not know how to go there. He will tell you how to deal with it. 在不定式作宾语时，有时我们会使用 it 作形式宾语，而把不定式放到后面。如：They consider it inappropriate to have classes in the evening. （4）可以作形容词的宾语。这一类形容词有 glad, sorry, afraid, pleased, determined, willing, eager, anxious 等。例如：I”m determined to give up smoking. He is willing to help us. （5）在 tell, advise, allow, forbid, learn, show, decide 等词的后面常用“连接词+不定式”作宾语。 例如：We must decide whether to go or stay. I don”t know how to get in touch with him.3.不定式作表语不定式作表语时，主语通常是一个名词，不定式短语或者从句。The bosss plan is to start building the skyscraper immediately. To work means to earn a living. What you have to do is to push the button.4.不定式作定语不定式作定语相当于一个定语从句，它修饰以下几类名词：由动词派生或转化而来的名词，它们所对应的动词通常有不定式作宾语。这类名词主要有：attempt， claim， decision， plan， promise， intention， need，resolution，tendency， wish， failure， threat 等。Another attempt to climb the mountain will be made next month. In his speech he expressed his determination to achieve the goal. 由可能与不定式搭配的形容词派生出来的名词。这类名词主要有：anxiety， patience， ability， willingness， ambition 等。Her eagerness to learn a foreign language obvious. 不定式作定语还可用来修饰代词 something， anything， everything， nothing.不定式做后置定语。 Do you have anything to send? 你有什么东西要寄吗？（不定式 to send 的动作执行者是 you） Do you have anything to be sent? 你有什么要（我或别人）寄的东西吗？不定式 to be sent 的动作执 行者是已被省略的 me 或 someone else）She has everything to lose and nothing to gain. 由 only， last， next， 序数词或形容词最高级修饰的名词后常用不定式作定语。Jim is the only student to answer the question correctly in his class.You are the last to undertake the blood test. 不定式常作为定语修饰 there be 结构的真实主语。在 there be 结构中，用来修饰主语的不定式有时用主 动形式，有时用被动形式。当说话人考虑的是必须有人完成某件事时，不定式用主动形式。如果说话人强调的 是事情本身必须被完成时，不定式则用被动形式。例如： There is a lot of work to do.（Somebody has to do the work.） There is a lot of work to be done.（The work has to be done.） 有些抽象名词。主要有：reason， right， time， effort， chance， way 等。如： the time to go to school， the way to get to the clinic， the chance to win the game. (7)如果不定式中的动词是不及物动词,则不定式中要有介词.I have something to say. He has a lot of homework to do . He is looking for a room to live in . There is nothing to worry about. 不定式所修饰的名词或代词是不定式动作的地点工具等，即使是及物动词，不定式后面仍须有相应的介词。 Please give me a pen to write with. 不定式所修饰的名词如果是 time, place 或 way，不定式后面的介词习惯上要省去。 He had no money and no place to live. 他没钱没地方住。 (8)不定式作定语时，应放在被修饰词的后面，而且放在其他后置定语之后。不定式做定语与所修饰的词之 间有三种关系： 1)动宾关系 I have a lot of work to do.我有很多工作要做。 2)主谓关系 He is always the first to come.他总是第一个来。 3)同位关系 We all have a chance to go to college. 我们都有上大学的机会。5.不定式作状语不定式作状语相当于一个状语从句，表示形为的目的、结果或原因。表示目的。在这种情况下，不定式的逻辑主语通常也是全句的主语。He stayed there to see what would happen. 在强调不定式目的状语时，不定式前可加 in order， so as 等。如：She asked me to drive her to the airport in order to catch the 5：00 plane.He moved the TV set to the meeting-room so as to let everyone watch it.用 soas to， such （） as to， enough to， tooto， only to 等表示结 果，如：Have you got enough room to seat all of us？She is too weak to join us in the outing.将不定式移到句首表示条件，如：To hear the teacher better， you have to sit in the front. = If you are to hear the teacher better，与形容词连用时，大多表示原因。这些形容词主要有：happy， kind， surprised， frightened， angry， shocked， glad， delighted， grieved，disappointed 等。They were surprised to be informed of the news. Im glad to hear this. 6、独立结构To tell the truth, I dont agree with you. to be frank, to be honest, to tell the truth 7、关于小品词 to (1).不定式中的动词上文已出现过,下文要省略该动词.eg: Would you like to go with me ? Id like to . (2). 不定式是 to be 结构, be 不可省.eg: Would you like to be a teacher? Id like to be. 不定式与疑问词 who,which, when, how, what 等连用，在句中起名词作用，可充当主语、表语、宾 语等。 He didnt know what to say.他不知道说什么。(宾语) How to solve the problem is very important.如何解决这个问题很重要。(主语) My question is when to start.我的问题是什么时候开始。(表语