Hu Juren, a scholar of the Ming Dynasty: If there is constancy, why sleep at three o'clock and get up at five o'clock? The most useless thing is to be exposed to ten days of cold in one day.

Mao Zedong: If you have permanence, why do you need to sleep at three or five o'clock? The most useless thing is that it will be cold for ten days in one day.

In order to rescue Kong Rong, Taishi Ci first rested at home for three days, and then went out in high spirits.

Although it is a battle, it can also be used as an example for learning