摔倒在地上用英语怎么说

"fall down" 是摔倒在地上的英文表达。其来源是由 "fall" 和 "down" 两个词组合而成。

例句：

I fell down the stairs. (我摔下了楼梯。)
He fell down and hurt his ankle. (他摔倒了，伤了脚踝。)
She fell down and scraped her knee. (她摔倒了，擦伤了膝盖。)