一个灰色的回忆，怎能抗衡现在的生动与自由。
The world is indeed full of peril, and in it there are many dark places; but still there is much that is fair, and though in all lands love is now mingled with grief, it grows perhaps the greater.
"Innovation is born from the intersection of curiosity and necessity."
数学的目标是使简单的复杂化，使复杂的简单化。
The world is a stage, but the play is badly cast.