stone

The ancient castle was built using large blocks of grey stone from the nearby hills.

(Chinese) 这座古老的城堡是用附近山上的大块灰色石头建造的。

The boy picked up a smooth stone and threw it across the surface of the pond.

(Chinese) 小男孩捡起一块平滑的石头，把它扔向池塘水面。