初中英语语法三：动词不定式.pptVIP

* 英语专题：动词不定式 基本结构：to do; 否定式：not to do; 没有人称和数的变化；在句子中不能担当谓语 时态上：表示将来发生的动作 基本含义： 语态上：通常表示主动 (to be done) 表目的 Last weekend I went to the library _______ some books on how to protect the environment. A. to borrow B. borrow C. borrowed D. borrowing 动词不定式在句中除不能担当谓语外，可以充当其他任何成分，如主语、表语、宾语、定语和状语等 To get up early is a good habit. I should like to go with you. We have much work to do. He was too excited to say a word. To see is to believe. 用动词不定式作主语时，经常有it作形式主语，代替不定式，放在句子的开头，动词不定式则放在谓语的后面, 如： To get up early is a good habit. It is a good habit to get up early. (For us) To Learn English well is easy. It is easy for us to learn English well. 如果两个或两个以上的不定式并列使用，后面的不定式往往省略“to”。例如： I want you to stand beside me and hold the books. 常用不定式作宾语的动词有： afford 负担得起 agree 同意 ask 要求 refuse 拒绝 choose 选择 decide 决定 learn 学习 expect 期望 hope 希望 want 想要 wish 希望 fail 失败 promise 答应 pretend 假装 练习: 用所给的适当形式填空. My mother has promised ________ (take) me to the park this weekend. 2. I can’t afford ________ (buy) a car. 3. I hope ________ (stay) with you. 4. The teacher ask me ________ (clean) the classroom. 在had better, would rather后面的动词不定式不带 “to”,例如： You had better do it right now. You’d better not go there with them. 在表示感觉的动词如see, feel, watch, hear等及表示 “使役”的动词如make, let, have等后面，动词不定式 省去to；在动词help后面, 动词不定式可以带to，也 不以不带to: Don’t let the children play with fire. We watched him drive off. Food, sleep and exercise help children (to) grow. 有些动词，如want, like, wish, hope, try, ask, start, learn, agree, teach, decide, understand等，后面可以接连接代词或连接副词加不定式作宾语。 例如： No one could tell me where to get the book. 没有人能告诉我哪里能找到这本书。 Show us what to do. 告诉我们应该做什么。