矿工从矿层中开采出一大块煤。

The miner extracted a large lump of ___coal from the seam.

在一些地区，煤仍然是发电的主要燃料。

In some regions, ___coal is still the primary fuel for electricity generation.

工业革命严重依赖煤作为燃料来源。

The industrial revolution was heavily dependent on ___coal as a fuel source.