Answer: Long time no see. Long separation is a Chinese word, pronounced jiǔ, which is generally used for the etiquette of reunion after a long separation. Generally speaking, people who haven't seen each other for a long time are polite. From the Peach Blossom Fan.

Extension:

for instance

1, Biography of Peach Blossom Fan by Qing Kong Ren Shang: "Yang Zhu has been here for a long time."

2. Wu Qin Jingzi's "The Scholars" is the seventeenth time: "Zhao Xiong, long time no see! Where to go? "

3. Wang Tongzhao's "Crying in the Sky": "Ah, Grandpa Xiao Ran, long time no see, long time no see!"

Everything here is so strange and kind, and the long-lost happiness and long-lost relaxation have returned to me.

Baidu Encyclopedia-Long time no see