粗石

Knives can be sharpened by grinding them against a rough stone.

刀能在一块粗石上。

"The simplest stonework is rubBle, roughly Broken stones Bound in mortar. Ashlar work consists of regularly cut Blocks with squared edges."

简单的石料加工品粗石,在研机中粗略地破碎的石头。方石加工品整齐地切割出具方形边缘之石块所组成。