During the Three Kingdoms period, Zhong You was the first person to master lower case letters. He was originally a master of official script, and later he made small letters according to official script. The font is wide and flat, horizontal and short, and has the structural characteristics of official script. Later writers in lower case mostly took his lower case as a model. You can look at Wang Xizhi's Theory of Music and Yi, Cao Ebei, Huang Tingjing in the Eastern Jin Dynasty, and Wang Xianzhi's Thirteen Lines of Ode to Luoshen, all of which have such characteristics. In the Tang Dynasty, celebrities came forth in large numbers, such as Yu Shinan and Chu Suiliang's lower case letters, which developed to a certain height, especially Zhong Shaojing's Ling Fei Jing. You can go and see it sometime.
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