小河里有很多石头。

Xiǎohé lǐ yǒu hěn duō shítou.

There are many stones in the small river.

他坐在一块大石头上休息。

Tā zuò zài yí kuài dà shítou shàng xiūxi.

He sat on a big rock to rest.

他们在海边捡了很多漂亮的石子。

Tāmen zài hǎibiān jiǎn le hěn duō piàoliang de shízǐ.

They picked up many beautiful pebbles by the sea.