We must stop polluting the water.(划线部分提问)__must we stop____?划线部分是polluting the waterWe must stop polluting the water.(划线部分提问)____must we stop____?划线部分是polluting the water
问题描述：
We must stop polluting the water.(划线部分提问)__must we stop____?划线部分是polluting the water
We must stop polluting the water.(划线部分提问)
____must we stop____?划线部分是polluting the water
答
What must we stop doing?
答
what doing
答
polluting the water 是件事,可用what 代替
stop 后加 doing 表停止做某事
所以
what must we stop doing?