同时根据贫煤的资源量和使用范围，使用贫煤具有良好的经济效益。

Considering its rich resources and utilization range, people find lean coal has excellent economic benefit.

youdao

同时根据贫煤的资源量和使用范围，使用贫煤具有良好的经济效益。

Considering its rich resources and utilization range, people find lean coal has excellent economic benefit.

youdao