Originally, it was passed down from generation to generation, such as respecting two leaves. -Korea's "Qiu Liu Kuanbei" follows the former Ye De, which is very peaceful. -Korea's "Yuzhou engages in Confucius Monument" has lived in Shu for a long time and has been tired of leaves. -"Shi Shuo Xin Yu"
Later, it turned into a historical stage, with early leaves as the initial stage (the first 30 years), middle leaves as the middle stage (40-60 years) and late leaves as the late stage (70- early next century).