考点解读
1、不定式知识点综述
2、不定式重难点讲解
重难点1：动词不定式的时态语态
动词不定式(infinitive)两种形式：一种是“to + 动词原形”构成（to- infinitive）；另一种是不带to的不定式,即动词原形(bare- infinitive)。动词不定式有一般式、进行式、完成式、完成进行式四种时态变化形式，一般式和完成式有被动语态变化形式。
a. 不定式的时态是以句中谓语动词的时间为依据的：
（1）一般式表示的动作或状态通常发生在谓语动词之后或同时发生。
例：They made plans to live in Paris.他们计划住在巴黎。（to live 发生在 made plans之后）
（2）进行式表示其动作正在进行，与谓语动词发生的动作同时进行。
例：He pretended to be listeningto me carefully. 他假装认真地听我讲。
（3）不定式的完成式所表示的动作或状态发生在谓语动词所表示的动作之前。
例：I am sorryto have kept you waiting. 对不起，让你久等了。
（to have kept发生在I am sorry所表示的时间之前）
（4）不定式的完成进行式表示动作在谓语动词之前发生，而且一直进行着。
例：He was happy to have been staying with his uncle.他很高兴一直跟他叔叔住在一起。
b. 不定式的语态
不定式的时态是以逻辑主语为依据的：
例：The sports meeting on the weekend has to be put off. 周末的运动会被迫推迟。
注意：意义上被动形式上主动的不定式
在“名词（代词）＋ be easy(difficult, fit等形容词) ＋ 不定式”结构中，有时尽管主语是动作的承受者，不定式在意义上是被动，形式上却是主动，这时可以看成省略了动词逻辑主语for us, for me , for you 等。
例：The book is difficult to read. 这本书很难读懂。
重难点2：动词不定式作主语
不定式及不定式短语作主语时，为了平衡句子结构，可用it作形式主语，而把真正的不定式后置。在下列情况下只宜采用it作形式主语
（1）当句中谓语动词不是be, seem, appear等连系动词时。
例：It took us 20 minutes to get to the station.赶到车站花了我们20分钟。
（2） 在“it +be + adj. + of/for + sb. +不定式”结构中。如果句中的形容词表示人物特征或品质，常同of搭配构成“It is + 形容词＋of＋代词（名词）＋不定式”句型。如： bold ，brave, careful, careless, considerate, cruel, rude, generous, :right，wrong, kind，nice，good，polite，clever，wise， foolish, silly等；表示事物性质的形容词如easy, difficult, hard, important, impossible, possible, safe, dangerous, necessary常同for 搭配。
例：It"s very nice of you to help me with my work.帮我的工作，你真是太好了。
重难点3：动词不定式作宾语
（1）有些及物动词常跟不定式作宾语，如agree, afford, arrange, ask, begin , decide, forget, hope, like , start , want, wish, threaten, pretend, promise, plan等。也可用来作形容词的宾语，如able, afraid, anxious, careful, content, determined, eager, foolish, free, glad, inclined, likely, pleased, prepared, ready, slow, sure, sorry, willing等。
例：The boys and girls are anxious to learn how to swim. 孩子们渴望学会游泳。
（2）不定式作宾语时，句子的主语是不定式的逻辑主语，与不定式动词的关系是主动关系，但有时不定式和主语却是动宾关系。
例：English is not difficult to learn.英语不难学。
（3）feel, find, judge, make, think, believe, consider等动词后如果是不定式作宾语，后面有宾语补足语时，将真正的宾语不定式放在补足语的后面，而将形式宾语it放在补语之前。
例：I thinkit our duty to support the elder.我认为赡养老人是我们的义务。
(5) 关系词+动词不定式
动词不定式可以和疑问代词：who, what, which 及疑问副词：when, where, how, why等连用，构成不定式短语，在句中作主语、宾语、表语等成份。如：
例：He showed mehow to use a computer. 他向我示范了一下怎样使用计算机。（宾语）
重难点4：动词不定式作定语
不定式作定语时，需放在它所修饰的名词或代词之后。它与所修饰的名词或代词有下列关系：
（1）“the last/next/first...” 后常接不定式作定语
例：He is always the first to come and last to leave.他总是第一个来，最后一个走。
（2）常用不定式作定语的名词opportunity, desire, promise, permission, chance, option, decision, plan, attempt, ambition, ability, obligation, tendency等。
例：The farmers thought of ways to protect their crops. 农民们想出保护庄稼的办法。
重难点5：动词不定式作状语
不定式作状语时，常表示目的、结果、原因、条件等，通常放在它所修饰的动词之后。常考不定式作目的和结果状语。
（1）表目的
不定式作目的状语时，其动作发生在谓语动词之后，一般放在句子后部。但如要表示强调，也可以位于句首，前面可加in order,不定式作目的状语时其否定必须用in order not +不定式，或so as not ＋不定式。in order to 引出的不定式可置于句首或句中，so as not＋不定式不能放在句首，只能放在句中。
例：We often listen to English broadcasts to/in order to/so as to get listening training.
（2）表示结果
a. 形容词如right, polite, crazy, generous, good, greedy, kind, selfish, silly, splendid, nice, unselfish, unkind等对人进行表扬或批评，后接不定式表示结果，不定式的逻辑主语也就是句子主语。
例：He is very polite to show us the way.他很有礼貌给我们指路。
b. 不定式和only连用，表示未预料到的结果。
例：The thief broke into the house only to find it empty. 小偷闯进屋子，却发现是空的。
c.在so… as to, such …as to, enough to等结构中的不定式皆表示结果。
例：He is too young to join the army. 他太年轻了，不能参军。
d. “too …to”表示结果意为：太……而不能……，但有时不含否定意义。
例：He is too excited to sleep. 他太激动了，不能入睡。（否定）
We are only too pleased to work together with you.我们同你一起工作，真是太高兴了。（肯定）
除此之外还有一些固定结构：
to be brief 简而言之、to be exact 精确的说、to be frank with you老实对你说 、to be plain 老实说 、to put it straight直截了当、to bring the story short长话短说、to return to my subject言归正传、to change the subject换一个话题、to use his own words用自己的话说、to make matter worse更糟的是、to give him his due公正地说、strange to say奇怪地说、to say nothing of姑且不讲、to conclude总之、to crown all更好（坏）的是、to be honest直率地说、to start /begin with首先、to do him justice说句公道话、to sum up总之，总而言之等。这些短语大都位于句首，偶尔位于句中或句尾，需要用逗号和其他成份隔开。但表示“更不用说”的几个短语一般要放在句尾，如to say nothing of, not to say, not to mention, not to speak of, let alone, much less, much more 等。
重难点6：动词不定式作宾语补足语
动词believe, consider, declare, find, prove, suppose, feel, think等后面常跟to be 不定式作宾补。有时to be 可以省略。这类不定式改为被动语态后就变成了主语补足语。感官动词如feel, see, hear, watch, notice, observe, listen to, look at 等以及使役动词make, have, let 等在跟不定式作宾语补足语时省略不定式符号to。但在转换成被动语态时要加上to。
例：He was heard to sing next door.有人听见他在隔壁唱过歌。
She made the boy go to bed early.她让那个男孩早睡觉。
重难点7：动词不定式的省略
不定式除了与助动词（be going to, be to 等除外）、情态动词（ought to, used to等除外）连用时不带to外，下面几种情况通常也不带to：
(1) 当两个或两个以上的不定式具有同等功能时，往往由and，or，than等连接，只用在第一个不定式前，第二个(之后的)不定式可以省略to。
例：It is easier to praise people than criticize them.表扬人比批评人容易。
（2）在had better, had best, would rather… than, rather than, would sooner, would sooner… than, cannot but, cannot help but等结构中后面不用to
例：He would rather die than give in.他宁死不屈。
（4）Why(not)后不能带to
这种结构的肯定式表示不满或委婉的批评，否定句则表示指责。
例：Why not think of something you can do.为什么不想个你能干的事呢?
（5）在feel, hear, notice, observe, see, watch等感官司动词后，have, make, let等使役动词后作宾语补足语时，不定式不带to。如：
例：He notices a thief slip into the house. 他注意到一个小偷溜进了房子。
（6）在某些介词后
介词except， but，besides之后跟不定式作宾语时，如果介词前有动词do及其变化形式时，不定式省略to（前有do后省to）。
例：I"ll do anything but help the boy with his lessons.除了帮那孩子做功课外，我什么都干。
典型例题
The students are looking forward to having an opportunity(explore) society for real-life experience. (2013年上海英语高考)
【答案】to explore
【解析】此处是考察不定式作定语，常用不定式作定语的名词opportunity,desire, promise,permission,chance,option,decision,plan,attempt,ambition,ability,obligation,tendency等。
As Jack left his membership card at home, he wasn"t allowed(go) into the sports club. (2012年上海英语高考)
【答案】to go
【解析】此处考察非谓语动词作宾语补足语，后接不定式作宾语补足语的动词有advise/allow/admit/permit/forbid/consider/recommend（为了方便记忆可以用首字母缩写FaPaCaR），这几个动词后接动名词做宾语。本题考察allow sb. to do, 变成被动语态sb. be allowed to do。
Today we have chat rooms, text messaging, emailing… but we seem ______(lose) the art of communicating face-to-face. (2011年上海英语高考)
【答案】to be losing
【解析】系动词后用不定式做表语，此题的难点是要考虑不定式的时态和语态。根据句意‘因为有了聊天，短信，面对面交流的艺术逐渐开始衰退’可知此处用不定式的进行比较恰当。
Thai is the only way we can imagine (reduce) the overuse of water in students" bathrooms. (2010年上海英语高考)
【答案】to reduce
【解析】分析句子结构可知we can imagine为定语从句，在解题时可以省略不看，根据句意可知本处考查不定式做目的状语。本题的易错点在于，学生看到imagine会认为考查动名词做宾语，因此会误填reducing，一定要引导学生进行正确的句子结构分析。
David threatened ______
(report)
his neighbor to the police if the damages were not paid.
(2009年上海英语高考)
【答案】to report
【解析】此处考察非谓语动词作宾语，后接不定式作宾语的动词有agree, afford, arrange, ask, begin , decide, forget, hope, like , start , want, wish, threaten, pretend, promise, plan等。
学法点睛
1、专题特点和学习方法
不定式是高考中常考的一种语法形式，通常出现在语法新题型中和翻译中，常考作主语、宾语、宾语补足语和状语的语法功能。在学习时要了解不定式词的形式：to do, to be done, to be doing; to have done, to have been done，对各种形式的用法要清楚；注意跟其他两种非谓语形式进行区分，如动名词和不定式作宾语的区别等，重点要对一些不定式作宾语的动词、定语、宾语补足语的动词进行识记。
2、解题技巧
理解不定式的几种基本形式的用法和区别，学会根据不同的语境选择适当的形式，主要从时态和语态两方面判断，语态找逻辑主语（不定式作宾语和状语时逻辑主语为句子主语；作宾语补足语时为宾语；作定语时为所修饰的词），时态比较跟谓语动词的先后顺序（先于谓语动词用完成式；同时用进行式；在谓语之后发生用一般式表示将来）；
过关检测
巩固测试（高考真题改编）
1. If there"s a lot of work______(do), I"m happy to just keep on until it is finished. (2008)
2. There is nothing more I can try ______ (persuade) you to stay, so I wish you good luck. (2007)
3. The mother felt herself __________ (grow) cold and her hands trembled as she read the letter from the battlefield. (2006)
4. Energy drinks are not allowed __________ (make) in Australia but are brought in from New Zealand. (2006)
5. It was unbelievable that the fans waited outside the gym for three hours just ____ (have) a look at the sports stars. (2005)
6. The flu is believed _______ (cause) by viruses that like to reproduce in the cells inside the human nose and throat. (2004)
7. An army spokesman stressed that all the soldiers had been ordered (issue) clear warnings before firing any shots. (2003)
8. In order to gain a bigger share in the international market, many state-run companies are striving __________ (make) their products more competitive. (2002)
9. With a lot of difficult problems (settle), the newly-elected president is having a hard time. (2002春)
10. Do let your mother know all the truth. She appears _____ (tell) everything. (2001)
11. There are five pairs _______ (choose from), but I’m at a loss which to buy. (1999)
12. --- Mum, why do you always make me eat an egg every day?
---_______ (Get) enough protein and nutrition as you are growing up. (1999)
13. A computer does only what thinking people have it ________ (do). (1999)
提升测试：(近三年模拟题单选改编)
1. I’d like to see your problem ________ (solve) before the end of this term. (2013年一模)
2. Mercedes is the first team ________ (win) the race this year, following Button’s victory in Australia last year. (2013年一模)
3. A reporter’s task is to inform readers of the events that happened, ________(draw) conclusions. (2013年一模)
4. A total of 264,302 people in the country were reported ________(infect) with HIV by the end of last September. (2013年一模)
5. The government will come up with more volunteer projects just ________(promote) the volunteer industry. (2013年一模)
6. The students expected there _________(be) more reviewing classes before the final exams. (2013年一模)
7. A red light is a warning to drivers and staff that another train is dangerously close and that adjustments need _________ (make). (2012年一模)
8. Many farmers in the countryside have gone to cities to look for work and left their children behind ______ (raise) by their grandparents. (2012年一模)
9. I have tried everything I can _____ (persuade) him to stay, but without success, so I wish him good luck. (2012年一模)
10. After finishing the lecture, I started to listen to my student _______（discuss）the social problems mentioned in my lecture. (2012年一模)
11. ______ (prevent) global temperature rising, the UN Climate Change Conference was held in Cancun, Mexico last year. (2012年一模)
12. Having lived all by herself for many years, the old lady is sometimes very difficult______(get) along with. (2011年二模)
13. The first black president of the United States of America, Barack Obama, won the election in the end, but it remains, of course, _________(see) whether he can overcome the present difficulties. (2011年二模)
14. It is the duty of a teacher _____ (stimulate) the interest of students and pass on knowledge to them. （2012年二模）
15. What people learned from China Got Talented was that there were so many talented people out there waiting ______(discover). （2012年二模）
【参考答案】
巩固测试：
to do, to persuade, grow, to be made, to have, to be cause, to issue, to make, to settle, to be told, to choose from, to get, do
提升测试：
to win, to cope with, not to draw, to have been infected, to promote, to be, to be made, to be raised, to persuade, discuss, to prevent, to get, to be seen, to stimulate, to be discovered
