是fall的过去式。

v. 落下跌倒下垂跪下（地面）向下倾斜（数量等的）减少 （雨或雪） 降落沦陷 阵亡进入（某状态）突然来到

n. 落下跌倒（雪、岩石等的）降落（数量等的）减少秋季垮台、衰败Spots of rain had begun to fall.

雨点已经开始落下来了。

Aren't you afraid (that) you'll fall?

你不怕会跌倒吗

Output will fall by 6%.

产量将下降6%。

He was terrified (that) he would fall.

他很害怕会跌倒。

She broke her right leg in a bad fall.

她在一次严重的跌倒中右腿骨折了。