壁炉里堆满了煤块。

The fireplace was stocked with lumps of ___coal.

开采金、煤或石油是我们经济的一个选择。

Mining for gold, ___coal, or oil is an option for our economy.

许多发电厂仍然依靠燃烧煤来发电。

Many power plants still rely on burning ___coal to generate electricity.