"The essence of mathematics lies in its freedom."

The most profound ideas in mathematics often arise from the simplest observations.

煤炭行业要坚定不移地走安全高效、清洁低碳的发展道路。

I am not a hero, I am just an ordinary person.

Teachers are the most important role models in schools, the most instructive examples, and the most vivid examples for students.

The aim of life is to live, and to live means to be aware, joyously, drunkenly, serenely, divinely aware.

小小的善举比你可能预期的更能提升你的情绪。