The sustainable development of the coal industry requires the coordinated efforts of policy, technology, and the market.

Sustainability isn't just about planting trees; it's about planting the right trees in the right places for the right reasons.

花儿凋落随水流去，带着淡淡的红色，心中有无尽的闲愁，默默无言地埋怨着东风。

"Books are the quietest and most constant of friends; they are the most accessible and wisest of counselors, and the most patient of teachers."

所有事情在被证明为不可能之前都是可能的，甚至不可能的事情也可能只是目前如此。