Outlined by rays of sunlight known as crepuscular rays, they are actually shadows cast by clouds near the distant western horizon, the setting sun having disappeared from direct view behind them.

在被称为曙暮辉的太阳光线的照射下，它们实际上是由靠近遥远的西方地平线的云层产生的阴影，此时落日在云层的正后方渐渐隐去。

youdao

I know that the sun always eventually shines through the clouds, and when it doesn't you learn to dance in its shadows and in the rain like glitter is falling from the sky.

我知道太阳最终总能穿透乌云，没阳光时你要学会在阴影下在雨中舞蹈，就像星星坠落天空。

youdao

The challenge is to pick out oil from other dark spots, such as shadows made by clouds or patches of seaweed.

VOA: standard.2010.07.05

Nameless waterfalls tumble down from the plateau above, while the shadows of clouds dance across treeless slopes.

BBC: An Icelandic journey to the centre of the earth