新人教版八年级下册英语动词不定式详细解析.ppt

人教课标版 八年级英语（下册） 课题：动词不定式的用法 知识回顾 比较下列两组句子 第一组: Every morning I keep on running. He likes playing tennis after school. 第二组: My friends want me to go out with him. Jack invites me to go shopping. 不定式定义及构成 (一) 动词不定式定义: 动词不定式是指动词的一种不带词形变 化从而不指示人称、数量、时态的形式，属 于非谓语形式。 (二)动词不定式构成： to +动词原形 省“to”的不定式 to+动词原形 A: I want to buy some books. B: They wanted to buy some books. C: He decides to go home by himself. 动词后省to的不定式 (一)感官动词： see, watch, notice, look at，hear, listen to , feel . A: He saw some birds fall into the river. B: I often hear the girl sing in the next room. C: They looked at that person go into the store. 动词后省to的不定式 (二)使役动词: make, let ,have. A: My mother makes me go to school . B: Let the boy go . 动词后可省可不省“to”的不定式 (三) 特殊动词Help A: I often help my mother do house work. B: My classmates help me to learn English. 不定式的否定形式 1.带to的动词不定式的否定 I want you to go now. I want you not to go now. 直接在“to”前加not 2.省to的动词不定式的否定 Let the boy go out . Let the boy not go out . 直接在动词前加not 动词不定式用法 动词不定式放在一些动词后面可以作宾语、 宾语补足语、目的状语、表语等。 动词不定式用法 (一) 动词不定式作宾语 动词不定式可以放在一些动词后用作宾语，动 词不定式作宾语的常用动词有:begin ask ,want ,forget ,remember ,learn ,hate 等。 A：I want to go home now . B: She forgets to take some medicine. C: My mother learns to dance. 不定式作宾语结构 Want to do sth Need to do sth Decide to do sth Learn to do sth Wish to do sth Try to do sth Hope to do sth Plan to do sth 练习 A: 我想买一些书。 I want to buy some books. B: 他们需要做更多的运动。 They need to do more exercise. C: 他希望离开学校。 He hopes to leave school. 动词不定式用法 (二)动词不定式作宾语补足语。 动词不定式作宾语补足语表示宾语所做的动 作，可以用动词作宾语补足语的动词有： tell ,ask ,want ,invite ,expect,help等。 A: I want you to go now . B: Her parents wish her to be a teacher . C: He invites me to go swimming . 动词不定式作宾补结构 Ask sb to do sth Invite sb to do sth Tell sb to do sth Expect sb to do sth Want sb to do sth Wish sb to do sth