There is a short poem about clouds.

I am a cloud in the sky,

Occasionally projected into your heart—

You shouldn't be surprised,

There's no need to be happy-

It disappeared in an instant.

You and I met in the dark sea,

You have yours, I have mine, direction;

You remember it well,

You'd better forget,

The light that shines on each other at this intersection!

-Xu Zhimo's "Accidental"