数学的真正力量不在于它的复杂性，而在于它的简洁和优雅。

The true teacher defends his pupils against his own personal influence.

The future of coal lies in clean and efficient utilization.

Never underestimate the power of persistence. Most people give up too soon.

构思得好的东西表达得也清楚，表达的文字也很流畅。

"Mathematics is the science of patterns, and we study them to learn how to think logically, critically, and creatively."

有时看前来像是解决方案比问题多。仔细观瞧，今天的很多问题都是昨天的解决方案带来的结果。