hot coal gas

例句：

1. 1. The factory uses a lot of hot coal gas to power its machines.
   这个工厂使用大量的热煤气来驱动机器。
2. 2.The hot coal gas was released into the atmosphere, causing a significant amount of pollution.
   热煤气被释放到大气中，造成了相当大的污染。
3. 3. The workers were forced to wear masks while working in the hot coal gas area.
   工人们在高温的煤气区域工作时被迫戴上口罩。