数学不是一项观赏性运动;要理解它,必须积极参与其中。
地理学是关于地方的科学,而不是关于人的科学。
你离死亡越近,就越能感觉到活着。
The past shapes the present, and the present shapes the future.
I’ve had to work very hard for every title. Nothing has been given to me.