Bill(fell down)some steps but fortunately he didn't hurt himself badly.

问题描述:

Bill(fell down)some steps but fortunately he didn't hurt himself badly.
请问这里的fall down是一个词组吗?
怎么理解呢?有相关例句最好了

fall down 倒下,摔倒
Several trees fell down in the gales.
好几颗数载那场风暴中倒下了
The boy hit the tree to hard that he fell down.
男孩重重地撞在树上,结果自己倒下了.
If people run across the road,they may fall down.
如果人们跑过马路的话,他们可能会摔倒.
还有一个意思,失败.
本题是第一个意思