三、动词不定式作宾语.即不定式直接跟在谓语动词后,是谓语动词涉及的直接对象.如果没有这个不定式,这个句子的意思就让人难以理解. 能直接带不定式作宾语的及物动词主要有: want, like , love , need , try , ask , learn , begin , start , forget , remember, hope , wish , agree, choose , fail , refuse , decide , afford , offer , make sure , take turns , would like , plan , hate , try one’s best 等.
四、动词不定式作宾语补足语. 能用动词不定式作宾语补足语的动词有: ask , tell , get , order , would like , want , teach , show , allow , encourage , warn , wish , invite ,help等.
五、动词不定式作状语: 即不定式直接跟在谓语动词后,仅对谓语动词起一个补充说明的作用.如果没有它,句子仍然意思完整,它不象作宾语那样,与谓语动词有着密切的关系.(1)表示目的: The doctor came to operate on her. He has gone to town to do some shopping. I sat down to have a rest. He stopped to have a look. He rushed into the room to save the girl. The moved away the stone to let the traffic go. He got up to catch the train.
(2)表示结果: The girl cried only to make her mother angry.
(3)表示程度: She is too tired to walk any farther. She is strong enough to carry the heavy box.
六、不定式作定语: 动词不定式作定语,一般要放在被修饰词的后面,不定式与所修饰的词构成动宾关系. We have lots of work to do. Would you like something to drink? I want to get something to read during my holiday. That’s a difficult question to answer.
【注意】如果动词不定式是不及物动词,后面就应有必要的介词. 如: He is looking for a room to live in. Give me a piece of paper to write on. He has nothing to worry about. There is not enough space to stand in on the earth.. She is a nice person to work with. a place to go to.
七、动词不定式作主语: 如 To learn a foreign language is not easy.
在现代英语中,常用it来作形式主语,而把真正的动词不定式主语放在后面.即句型:
“It is+形容词+for ( of) sb. to do sth.”中,当形容词是kind ,nice , good , clever , careful , careless , right , wrong , foolish 等表示人的性格特征时, 用of ; 如果形容词为difficult , easy , hard, important ,interesting, possible ,necessary 等表示事物的特征时, 用for. It is necessary / important / easy / hard/ possible for us to learn English well. It is very kind /nice / good of you to help me with my English.
※ 在句型: 主语+find / think / feel / make +it +形容词+ to do sth.中,it为形式宾语.
I found it very important to learn English well. I think it easy to learn English well.
八、作表语: My job is to teach English. His wish is to become a scientist.
九、动词不定式和疑问词连用.动词不定式可以和疑问词what, which , how , when , where ,who 等连用,构成不定式短语,在句子中作主语、宾语、表语等成分.这时往往可以扩写成宾语从句; The question is how to use the computer.
I don’t know where to go for my holiday =I don’t know where I can go for my holiday.
He can’t decide which book to choose.= He can’t decide which book he can choose.
I don’t know what I should do next=I don’t know what to do next.
十、动词不定式的否定形式: not to+动词原形
Tell him not to be late. I will try not to read in bed.
十一、动词不定式省略to的场合:(1)作动词let, make , have, feel ,hear, see , watch , notice 等的宾语补足语时,动词不定式不带to. Let him do the work. He made me work day and night. I saw him fall off the bike.
(2)作动词help的宾语补足语时,动词不定式可带to,也可不带to.
He didn’t help me(to)mend the bike. You have helped ( to ) protect our environment.
(3)在助动词和一些情态动词如will , would , shall , should , can , could , may , might , must , do , does , did , didn’t , don’t , doesn’t 等的后面,用动词原形,即动词不定式不带to.
Will you help me? He doesn’t live here. It might rain . You must finish your homework on time.
(4)在why not…? , had better , would rather 等的后面也跟不带to的动词不定式.(原形)
Why not buy a dictionary? You had better (not)stay at home. I would rather go early.
(5)在第二个不定式前一般不带to. I would like to lie down and go to sleep.
Do you want to eat now or wait till later?
※ 在下列答语中, to不能省略: -Will you join me in a walk?-I will be glad to.
-Will you go swimming with me this afternoon?-I would love to.
-Used he work in the factory?-Yes , he used to .
Exercises:
1. We must find a person (做这项工作)
2. In my family, my mother is always the first one (起床)