动词不定式

【来源：易教网 更新时间：2013-07-15】

  意义、形式和特征 

1)基本概念和形式动词不定式(infinitive)是一种非限定动词，由不定式符号to加动词原形所构成。动词不定式有动词的特征，同时也有名词、形容词和副词的特征。 

 2)动词不定式的动词特征  a)如果动词不定式是及物的，须有宾语。如：  He wants to study Japanese.他想学习日语。(动词不定式to study后面有宾语Japanese)  b)动词不定式可以被状语修饰。如：  The rain continued to fall heavily.雨继续下得很大。(动词不定式to fall后面有状语heavily)  动词不定式加宾语或状语构成动词不定式短语，如上二例中的to study  英语语法手册    第83页  Japanese和to fall heavily。 

3)动词不定式的非动词特征  用法动词不定式具有名词、形容词和副词的特征，所以它在句子中可用作主语、表语、宾语、定语和状语。 

1)主语  To lean out of the window is dangerous.把身子伸出窗外是危险的。 To talk with him is a great pleasure.和他谈话是一件非常愉快的事。 To die for the people is a glorious death! 为人民而死，虽死犹荣。 动词不定式短语作主语时，往往放在谓语动词的后面，而在句首用引词"作语法上的主语。上述两句即可改为：  It is a great pleasure to talk with him.  It is a glorious death to die for the people.  注意也常用"It is+形容词+动词不定式短语"这样的句型：  It is necessary to make a plan for this course of study.必须订一个学习这门课程的计划。  It is not difficult to learn a foreign if you spend time and effort on it. 小只要你花时间下功夫，学好一门外国语并不难。  It's just impossible to see that and not weep.看见那种情景而不哭是根本不可能的。(注意weep之前省去了to，以免重复) 

2)表语  Her wish is to become an astronaut.她的愿望是成为一名宇航员。 Our plan is to finish the work in two weeks.我们的计划是在两周内完成这项工作。  His only desire was to be useful to the country.他唯一的愿望是做一个对国家有用的人。

  3)宾语有些及物动词常用动词不定式作宾语。这些动词有want(想要)，wish(想望)，like(喜欢)，decide(决定)，help(帮助)，pledge(保证)，begin(开始)，forget(忘记)，learn(学习)，ask(要求)等等。动词不定式一般不作介词的宾语。如：  He wants to be a village school teacher in a mountain area.他要做个山村教师。  Do you like to watch football matches? 你喜欢看足球赛吗? Learn to walk before you run.先学走后学跑。  We decided to make changes in our plan.我们决定把计划做些修改。 动词不定式也可以用来作某些形容词的宾语。这些形容词通常只有ready(准备好，愿意)，eager(急于)，anxious(急于)等，但为了学习上的方便，也可以包括able(能够)，sure(一定)，glad(高兴)，sorry(难过)，afraid(怕)，free(随意)，pleased(高兴)，determined(决心)，willing(愿意)等。如：  He is sure to succeed.他肯定会成功。  英语语法手册    第84页  How do you do? I'm glad to meet you. 你好?见到你很高兴。  The boys and girls are anxious to learn how to skate.这些男孩子和女孩子渴望学会滑冰。

  4)定语动词不定式作定语时，须放在被修饰的名词或代词之后。如： He is always the first one to get up.他总是第一个起床。  I have a few words to say on this question。关于这个问题我有几句话要说。  They are discussing ways to guarantee high output.他们正在讨论保证高产量的办法。  After the Ching Ming Festival it is time to sow sorghum，millet and corn.清明节一过，正是播种高梁、谷子和玉米的时节。 

5)状语动词不定式作状语时，一般放在它所修饰的动词之后。 a)表示目的  He went to Beijing to study in 1988.一九八八年他去北京学习。 He went to Paris to learn French.他去巴黎学法文。  [注一]强调动词不定式所表示的目的时，动词不定式可变为in order to (为了)或so as to(以便)加动词原形。如：  We often listen to English broadcasts in order to get more practice in training our ears.我们经常听广播，以便加强听力训练。  In order to learn acupuncture，she practiced on herself every day.为了学习针灸，她每天在自己身上试验。(注意in order to可放在句首)  We must have good soil so as to grow roses.种玫瑰花要有好的土壤。 [注二]动词不定式可以放在句首，使其所表示的目的更加明显突出。如： To be a good teacher one must use good teaching methods.要成为好的教师一定要有好的教学方法。  To de fend our country we must strengthen ourselves.为了保卫祖国，我们必须自强不息。  [注三] 注意有些用作句子独立成分的习惯语，如to begin with(首先)，to conclude(最后)，to be sure(当然)，to tell you the truth(老实对你说)等。  b)表示结果  My grandmother lived to see the birth of my little daughter.我的祖母活到亲眼看到我的小女儿出生。  A few years later he came home to find that his hometown had greatly changed.几年后他回到家里，发现故乡的面貌大大地改变了。  [注一] 有时可以用too...to(太…而不能)结构来表示"结果办不到"。如： He is too young to join the army.他太年轻了，不能参军。 It was too cold，to go out last night.昨晚太冷，无法出去。 [注二] 动词不定式和only连用时，常表示未预料到的结果。如：  英语语法手册    第85页  I went to see him only to find him out.我去看他，不料他出去了。 I hurried to the post office，only to find it was closed.我匆忙赶到邮局，不料已经关门了