动名词起名词的做用,在句中可作:
1)主语:
Smoking is prohibited.
禁止吸烟。

2)表语:
My favorite sport is skating.
我最喜炊的运动是滑冰。

3)宾语或介词宾语:
I suggested going by boat.
我建议坐船去。
They insisted on going by plane.
他们坚持坐飞机去。

4)定语:
Give me my shopping bag.
把购物袋给我。
This is your boarding pass.
这是你的登机证。

在很多情况下可以构成合成词:
singing competition 歌咏比赛
wimming pool 游泳池
opening speech 开幕词
dining-car 餐车
waiting-room 候车室
milling—machine 铣床
sleeping-pill 安眠药片
coughing drops 咳嗽糖浆
deep—ploughing 深耕
close—planting 密植
weightlifting 举重
family—planning 计划生育

2.有些动名词已名词化,前面可以加冠词,可以用定语修饰,甚至有复数形式:
You should give the room a good cleaning.
你应该把房间好好打扫一下。
Who did the recording?
是谁录的音?
I have some shopping to do.
我得去买些东西。
The work needs careful planning.
这工作需要周密计划。
Please take our greetings to him.
请向他问好。

这种动名词可称为名词化的动名词。

3.有些动名词已完全成为名词
Let’s bring in the washing.
咱们去把洗的衣服收进来。
The story has a happy ending.
这故事有一个愉快的结局。