Question

英语问题，求助！

But my bike needs repairing.为什么repair要用ing形式？

Answer 1

need doing = need to be done
need 接动名词主动形式，表示被动意义、这时动名词和主语之间有动宾关系， need doing 可转换为 need to be done 结构，意思相同。如：
My hair needs washing badly. (= My hair needs to be washed badly.)
我的头发非常需要洗一洗。
The garden needs watering. (=The garden needs to be watered.)
花园需要浇水。

But my bike needs repairing.= But my bike needs to be repaired.

但我的自行车需要修理。

祝你学习进步，更上一层楼！ (*^__^*)
不明白的再问哟，请及时采纳，多谢！

追问

嘿嘿，谢谢你

追答

You are welcome.

Answer 2

need doing =need to be done

叫动名词表被动

这类的词还有want require

Answer 3

sth need(s) doing/need(s) to be done可表示被动，即某物需要被做，所以repair 需要用ing形式

Answer 4

need to be done=need doing
表示被动的特殊用法 ，小知识，知道就行

Answer 5

这里做名词用。否则要说needs to be repaired.