动词不定式 一看便会.ppt

动词不定式的作用 Functions of Infinitive 主语 (subject) 宾语 (object) 表语 (predicative) 定语 (attribute) 状语 (adverbial) 动词不定式归纳 一、不定式做主语时，谓语动词常常用单数 1、“To do …”放在句首做主语 eg: To drink enough water every day is very important. 2、如果动词不定式太长，常用it作形式主语“to do …”放在句末做真正主语，用“It”放在句首引导 eg.1：It is very important to drink enough water. eg.2: It takes you 5 minutes to get there. 不定式做真正主语的两个特殊句型 * It is/was +adj.+of sb. to do… eg: It is brave of him to save the girl in the water. 注意：在此句型中，adj. 只能用可以修饰行为、动作及人物的形容词。 例如：kind, nice, good, brave, clever, wise, stupid, foolish, honest, careless, cruel, generous etc. *It is +adj.+for sb.(用宾格) +to do… eg.1: It is not difficult for us to learn English well. eg.2: It is right for him to work here. 注意：这里的adj. 不能表示人的性质，只能表示某事或某物的性质。 例如：difficult, wonderful, meaningful, painful,useful 二、不定式作宾语 1、不定式经常放在及物动词，如：like, wish, hope, want, try, begin, start, mean, agree, refuse, promise, pretend等后面，表示请求、想要、打算、试图、答应、拒绝、假装做某事。 eg.1: Suddenly, it began to rain. eg.2: I’ll try to do my best. eg.3: I don’t mean to say we are perfect.(我并不是说我们是完美的。) 2. 一些动词要用wh-疑问词+ to do sth.作宾语，常见的动词有decide, know, learn, wonder, understand, find out, remember, see等 I don’t know what to do. how to do it. who(m) to ask/invite. when to stop where to go. I haven’t decided whether to sell it or not. She didn’t know which one to buy. We must find out what to do next. He didn’t remember when to start. 三、不定式作宾语补足语 1、不定式放在ask, tell, want, teach等动词后面。形式：名词/代词＋不定式 eg.1: The teacher told us not to be late for school. eg.2: My mother teaches me to learn English. eg.3: I asked him to help me. 2、help 后面的不定式标志“to”要省去 eg：They often help the grandma carry water. 3、 see, hear, watch, feel, notice, look at等表示感觉和let, make, have等表示使役的动词后面，不定式作宾语时要省“to” （注：被动语态不省to） 四、定语 (attribute) sth. to eat ( eat sth.) a room to live in (live in a room) 注意:不定式与被修饰的名词在逻辑上有动宾关系;如