moxa cone

例句：

1. 1. The mine is using moxa cones to control the gas flow.
   矿井正在使用煤柱来控制气体流动。
2. 2. The miners used moxa cones to create a safe working area.
   矿工们使用煤柱创造了一个安全的作业区域。
3. 3.The moxa cones were used as a temporary barrier during the construction.
   在建设期间，煤柱被用作临时屏障。