大学英语四级语法精要：动名词的句法功能

v+ing形式(现在分词及动名词)的句法功用

作主语:

walking is good exercise.
it’s nice talking to you.
there is no denying the fact that the new method has greatly raised labour productivity.

作宾语:

your shoes need polishing.
you mustn’t delay sending the tractors over.
he avoided giving us a definite answer.

作介词宾语:

动名词作介词宾语用的时候最多. 它常可以用在某些成语后面, 常见的有: insist on, persist in, think of, dream of, object to, suspect…of, accuse…of, charge…with, hear of, approve of, prevent…from, keep…from, stop…from, refrain from, be engaged in, look forward to, opposed to, depend on, thank…for, feel like, excuse…for, aim at, devote…to, set about, spend…in, get (be) used to, be fond of, be capable of, be afraid of, be tired of, be sick of, succeed in, be interested in, feel (be) ashamed of, be proud of, be keen on, be responsible for.

作表语:

the real problem is getting to know the needs of the people.

动名词和不定式都可以作主语或表语. 一般说来, 在表示抽象的一般的行为时多用动名词; 在表示具体某词动作, 特别是将来的动作时, 多用不定式.

作宾语补足语: 分词可以在see, hear, notice, watch, feel, find, keep, get, have等动词后作宾语补足语.

the words immediately set us all laughing.
once we caught him dozing off in class.
his remark left me wondering what he was driving at.

在see, hear, feel, watch, notice等动词后, 及可用现在分词, 也可用不定式构成宾语补足语. 用现在分词时, 表示动作正在发生, 用不定式时表示动作发生了.
do you hear someone knocking at the door?
yes, i did. i heard him knock three times.

作状语: 现在分词作状语时, 通常都表示主语正在进行的另一动作, 来对谓语表示的主要动作加以修饰或作为陪衬.

i ran out of the house shouting.
i got home, feeling very tired.
driving to chicago that night, i was struck by a sudden thought.

现在分词短语有时可以用作状语表示原因, 相当于一个表示原因的状语从句.
not knowing her address, we couldn’t get in touch with her.
seeing nobody at home, she decided to leave them a note.
having already seen the film twice, she didn’t want to go to the cinema.

现在分词短语有时可用作时间状语, 相当于when引起的从句:
seeing those pictures, he couldn’t help thinking of those memorable days they spent together.

如果两个动作是完全同时发生的, 多用when 或while加分词这种结构.
be careful when crossing the street.
when leaving the airport, they waved again and again to us.