Yan Zhenqing and Liu Gongquan were two great calligraphers in the Tang Dynasty. Their calligraphy works have literary influence, and their fonts are called Yan Ti and Liu Ti. Yan Zhenqing, a native of Shandong, inherited the tradition of his predecessors and absorbed the latest achievements of folk calligraphers at that time. He used ink horizontally and lightly, standing vertically, with a broad, dignified and steady glyph structure, showing the spirit of grace, generosity and openness. People praised his regular script as "swallow's head and swallow's tail", saying that the beginning of his pen path was round like a silkworm's head, and when he finished pressing the pen, he made a hard setback, then gently picked the tip, and the end was slightly forked, shaped like a swallow's tail. His unique artistic style of brushwork and glyph structure has created a new situation in China's calligraphy art.
Liu Gongquan, a native of Shaanxi, was born in Yan Zhenqing. He is good at regular script, pays attention to structure and form in writing, and uses a stiff pen instead of a stiff one. His words are bright and beautiful, vigorous and powerful, so he is called "Yan Gu". His writing emphasizes the importance of characters to the character of calligraphy. It is said that Tang Muzong asked him about his writing style, and he replied, "Use a pen in your heart, and your heart is always there." Liu Gongquan's famous copybooks are Mysterious Pagoda and Diamond Sutra.