conical ball mill

例句：

1. 1.The stone is a conical shape with a pointed top.
   这块石头是圆锥形的，顶部尖锐。
2. 2. The building has a conical roof that slopes down to the ground.
   这座建筑有一个圆锥形的屋顶，向地面倾斜。
3. 3. The cone-shaped rock was formed by the erosion of the riverbed.
   这个圆锥形的岩石是由河流侵蚀形成的。