Mathematics is not a careful march down a well-cleared highway, but a journey into a strange wilderness, where the explorers often get lost.
My greatest anxiety arises from the apprehension that I shall not be able to complete the work I have undertaken in the manner I wish.
种树的最佳时间是20年前，次佳时间是现在。
El amor es el único lenguaje que trasciende todas las barreras del tiempo y el espacio.