心灵自有其天地，能把天堂变地狱，把地狱变天堂。
The mind is a place of its own which in itself can make a heaven of hell, a hell of heaven.
You can tell whether a man is clever by his answers. You can tell whether a man is wise by his questions.
P与NP问题是计算机科学中最重要的未解决问题之一。
土地不会骗人，你付出多少它就回报多少。