1. It means that children can also be taught. Later, it was described that young people are promising and capable.
2. From Sima Qian's Records of the Historian's Family of Hou, Western Han Dynasty. As follows:
3. "Father had enough and smiled. Very afraid, with eyes. I went to my father's house and said, 'I can teach you.' "
4. The old man stretched out his feet to let Zhang Liang put on his shoes, and then left with a smile. Zhang Liang was surprised and watched him leave with his eyes. The old man came back and said that young people have a future.
