roll down the hill

The car began to roll back down the hill.

汽车开始倒着往山下滑。

《牛津词典》

For those of you who may not remember, Sisyphus, of Greek mythology, was the guy condemned to push a boulder up a hill, watch it roll back down, and repeat this for all eternity.

有些人可能不记得希腊神话里西西弗这个人了。他将一块巨石推上山顶，看着它从山顶滚下来，然后一生重复做这件事。

But with every roll, it picks up more and more snow until it becomes a big snowball rolling very fast down the hill.

但是随着每一次滚动，它会吸收越来越多的雪，直到变成一个大雪球飞快地滚下山。