The sun was falling behind the hills.

太阳落山了。

youdao

The round sun is falling west.

圆圆的太阳正向西落下。

youdao

Or, if you're in bright sun, use a light tent or white scrim to soften the light falling on your subject.

如果在明亮的阳光下，也可以使用柔光篷或柔光箱来柔化光线。

youdao

I kept saying to myself that when at last they found out about him, it will be like the sun falling out of the sky.

VOA: special.2010.03.27

"I kept saying to myself that when at last they find out about him, it will be like the sun falling out of the sky.

VOA: special.2009.01.03

Bellies full, we drove back down PR-184 following the falling sun toward the Caribbean Sea, cruising along the coast to reach Ponce, a colonial port town where long ago pirates raided Spanish ships coming into the harbour.

BBC: Puerto Rico��s Pork Highway

The sun is falling, silhouetting the forested skyline and covering our sails in its yellowy glow.

BBC: Sailing in Croatia

There was smoke and a terrible warmth, a gray sun rising and falling in what seemed like a matter of minutes, and the tiger, frenzied, dry-tongued, ran back and forth along the span of rusted bars.

NEWYORKER: The Tiger��s Wife