他在墙上画了一道彩虹。

Tā zài qiángshàng huàle yídào cǎihóng.

He painted a rainbow on the wall.

你看，天上有彩虹啊！

Nǐ kàn, tiānshàng yǒu cǎihóng a!

Look, a rainbow in the sky!

光线能反射出彩虹的颜色。

Guāngxiàn néng fǎnshè chū cǎihóng de yánsè.

Light can reflect the colors of the rainbow.