高中英语语法不定式.ppt

概述 动词不定式没有人称和数的变化，但有时 态和语态的变化，它仍有动词的特点，可以有 自己的宾语或状语，一起构成不定式短语。不 定式除具有动词的许多特点外，还具有名词等 特点，在句中可以做主语、宾语、表语、宾补 、 定语和状语，即除谓语外都能作。 用法： 1 作主语: 谓语动词用单数 To learn a foreign language is difficult. * 往往放在后面, 用it 作形式主语，不定式做真正的主语 。 It is difficult to learn a foreign language 2.作宾语： We agreed to meet here , but so far she hasnt turned up yet. * 有时用it作形式宾语，不定式做真正的宾语。 I finds it interesting to study English. I feel it my duty to help others. 作表语: 放在系动词be seem appear remain etc. 后面 Our plan is to finish the work in two weeks. seem/appear to do / to be doing / to have done Having a trip abroad is certainly good for the old couple, but it remains to be seen whether they will enjoy it. What I want to do is (to) break the world record. （如果主语部分含有实义动词do或do的某种形 式 ，表语不定式的 to 通常省略。） 作宾语补足语: He asked me to do the work with him. 接不定式作宾补的动词有 ask allow permit order tell advise expect wish force beg invite encourage persuade etc. * 在 feel hear, listen to have let make have see, watch , look at, notice, observe等词后面的宾语补足 语如果是不定式，要省略 to, 被动语态时必须加上 to I often hear him sing the song. He is often heard to sing the song. 作定语： （1）通常放在所修饰名词或代词的后面。 当被修饰的名词或代词是不定式的逻辑宾语，且不定式 的逻辑主语是句子的主语时，不定式用主动形式表达被 动意义。若不定式为vi.，其后应加上一个适当的介词。 Ive got a letter to write. He needs a room to live in. （2）序数词后作定语 She likes to listen to Mr. Lis lessons , so she is always the first to come and the last to leave. （3）the only 后作定语 (4) 最高级后作定语 but + 不定式 1 but 为介词，“除了” ， = except ，后跟不定式时 一般带to The bear had no choice but to lie down and sleep. The little girl said nothing but to cry. 2 but前如有实义动词do或do的某种形式，后面不定 式符号to要省略。 The little girl did nothing but cry. I have nothing to do but wait. 3 常用结构 cant help doing cant help but do have no choice but to do do nothing but do 动词不定式的时态和语态 一般式： 动词不定式表示的动作与谓语动词表示 的动作同时发生或在谓语动词之后发生。 He seems to know this. 同时 I hope to meet you again. 之后 进行式：动词不定式表示的动作和谓语动词表示 的动作同时发生，并强调动作正在进行。 He pretended to be sleeping when I came in. 完成式：不定式表示的动作在谓语动词表示的动 作之前发生。 I seem to have met you somewhere before. 完成进行式： 不定式所表示的动作先于谓语动作发生，并可能延续 下去。 She seems to have been reading the novel for three hours. 不定式逻辑主语 （1）一般是句子的主语。 He seemed to be reading something. (2)当需要明确指出不定式动作的执行者时，用for/ of 引出，逻辑主语用宾格形式，for/of本身无实际意义。 Its necessary for us to help each other. 有形容词作表语时： 当这些作表语的形容词能表达不定式的逻辑主语的品 行、性格、性质时，要用of brave careful careless kind nice good honest clever wise unwise stupid foolish rude cruel silly thoughtful impolite polite etc. It be + a . of sb. to do sth =sb/sth be + a. to do sth . It is very kind of you to say so. = You are very kind to say so. 当这些表语形容词不能说明不定式的逻辑主语，只能 说明不定式行为的是与非，重不重要等时： It be +a. for sb. / sth. to do. sb. / sth be + a . to do easy important difficult hard possible impossible necessary It is difficult for beginners to read the book. Beginners are difficult to read the book. 不定式省略问题 有时为了避免重复，省去不定式后面的内容，保留到 不定式符号to；如果是to be ， 保留到be；如果是to have done ， 保留到to have。 A Would you like to go to his