煤烟的

例句：

1. 1. The factory uses coal as its primary fuel source.
   这家工厂主要使用煤炭作为燃料来源。
2. 2. The coal mine is located in a remote area, making it difficult to access.
   这个煤矿位于偏远地区，难以到达。
3. 3. Coal mining has been a significant contributor to the country's economy.
   煤炭开采一直是该国经济的重要贡献者。