The best time to plant a tree was 20 years ago. The second-best time is now.
种一棵树最好的时间是20年前,第二好的时间是现在。
对于非礼的事,上等到的士人根本不想;对于非礼的事,中等的士人从来不说;对于非礼的事,下等的士人紧闭门户。
The true sign of intelligence is not knowledge but imagination.