This is called convention, also called "farewell", banquet etiquette. It used to mean offering sacrifices to the road gods, that is, offering sacrifices to ancestors ("ancestors" means "difficulties and obstacles"). Friends and relatives want to travel far away and hold a banquet to see them off as a sign of blessing and farewell.

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1, Tang Yangjiong's Preface: "The chicken mountain is full of law, and the farewell party is on the shore of Suyu; Green is a good friend, and his ancestors were sent abroad by Qingmen. "

2. Feng Ming Meng Long's History of the Eastern Zhou Dynasty, the seventy-first time: "(Zhuang) Jia was young, arrogant and extravagant, and all by luck, he disappeared completely. Besides, as a supervisor, I only respect potential enemies, and freedom takes precedence. They are relatives and guests in Japan, and they all have farewell parties. Jia Liulian drank good wine, and even the messenger advised him, he didn't care. "

3. The second time in Travel Notes of Lao Can: "The steward couldn't keep it again and again, so he had to set a farewell dinner that night."

4. Xia Yan's Biography of Qiu Jin Act I: "If you really want to study abroad, you have to let a few friends here know. Pick a day and I'll give you a farewell dinner, okay? "

5. The first paragraph of Lesson 25 "Farewell to the Yellow Crane Tower" in the first volume of Su Jiao Edition, the fifth grade of primary school: "In the spring and March of the following year, the Yangtze River was misty and flowered, and the young Li Bai boarded the Yellow Crane Tower to bid farewell to the great poet Meng Haoran."