A person must go through hard work to achieve something.

The performance standard must be Zero Defects. Not 'that's close enough'.

The essence of mathematics is not to make simple things complicated, but to make complicated things simple.

勇气不是没有恐惧，而是战胜恐惧。

世界上充满了自童年以来从未以开放的心态面对开放的门的人。