1, handed down from generation to generation, Chinese idiom, pinyin is X and xěn HuǒXiāng Chuán, which means that knowledge and skills are handed down from generation to generation.

2. From Zhuangzi. "Master": refers to the poor as a salary, and the fire spreads and I don't know what to do. The original intention is that the firewood is burned out, and the fire can still be passed down. In ancient times, it was a metaphor that bones were exhausted and the spirit was immortal; Later generations use it to describe the knowledge and skills passed down from generation to generation.