动词不定式讲义整理习题(附答案).doc

动词不定式 一、定义： 动词不定式的形式是to +动词原形,但to有时要省去。 不定式是一种非限定性动词。 非限定动词是指那些在句中不能单独充当谓语的动词，可分为不定式，动名词，分词。 不定式在句中不能作谓语。它具有动词的性质，本身可以带宾语和状语。 动词不定式在句中可以作句子除谓语之外的任何句子成分。动词不定式的被动形式除了一般形式外还有其完成式和进行式。 二、不定式的分类 (一) 带to的不定式结构 直接跟带to的不定式结构的动词主要有:want, ask, tell, hope, learn, try, decide, forget, remember, like ,love, stop, go, come等。 动词不定式的否定形式是在不定式前直接加not,即not to do sth. (二) 不带to的不定式结构 以下几种情况使用不带to的动词不定式: 1.下列词组后面的不定式不带to：would rather ...than（宁愿……也不）, had better...（最好），can’t help but...（不得不）, had rather...（宁愿）， cannot but...（不得不，必然），may/might as well...（不妨），let alone（更不用说）。 e.g.You’d better return the books to the library on time. Otherwise, you will be fined. 2.在let, make, see, feel, watch, hear等感官或使役动词后,要跟不带to的动词不定式作宾语补足语。 注意：在被动语态中则to 不能省掉。 I saw him dance. =He was seen to dance. The boss made them work the whole night.=They were made to work the whole night. 3.在引导疑问句的why not之后。 “Why not+不带to的不定式”是Why don‘t you do…的省略,可以用来提出建议或劝告。 Why not go with us? Why not take a holiday? 三、动词不定式的语法功能 （一）作主语 动词不定式作主语时，句子的谓语动词常用单数，其位置有以下两种： 1. 把不定式置于句首。如： To get there by bike will take us half an hour. 2. 用it作形式主语，把真正的主语不定式置于句后，常用于下列句式中。如： ①It＋be＋名词＋to do Its our duty to take good care of the old. ②It takes sb.+some time+to do How long did it take you to finish the work? ③It＋be＋形容词＋for sb＋to do It is difficult for us to finish writing the composition in a quarter of an hour. 在句型③中，常用表示客观情况的形容词，如：difficult, easy, hard, important, impossible, necessary等。 ④It＋be＋形容词＋of sb＋to do It is stupid of you to write down everything the man says. 在句型④中，常用careless, clever, good, foolish, honest, kind, lazy, nice, right, silly, stupid, wise等 表示赞扬或批评的词。 ⑤It seems (appears)＋形容词＋to do It seemed impossible to save money. (二)作宾语 以下动词后，只能跟不定式作宾语 Afford, agree, aim, appear, arrange, ask, attempt, care, choose, claim, condescend, consent, decide, demand, determine, endeavor, expect, fail, help, hesitate, hope, learn, manage, neglect, offer, plan, prepare, pretend, proceed, promise, prove, refus