每一个数学问题都是通向新理解世界的窗口。

In the global energy transformation, China's coal industry must have its own voice and contribution.

我一直在寻找挑战自己、推动自己更上一层楼的方法。

The only real failure in life is not to be true to the best one knows.

Thinking is behavior. The muscular habits learned in overt speech are responsible for implicit or internal speech (thought).