smoothing stone

例句：

1. 1. The smoothing stone is used to polish the surfaceof the wood.
   平滑石用于打磨木材的表面。
2. 2. The smoothing stone was used toremove the rough edges of the metal.
   平滑石被用来去除金属的粗糙边缘。
3. 3.The smoothing stone was used to createa smooth finish on the surface of thewood.
   平滑石被用来在木材表面创造一个光滑的外观。