2. Ou Yangxun is known as the first regular script in Tang Dynasty for his rigorous brushwork and precipitous brushwork. He and Yu Shinan were both famous for their calligraphy in the early Tang Dynasty, also known as "Ou Yu". Later generations saw danger in peace with their books, and Xi Zhi, the first one, was named "Ou Ti". Among them, Jiuchenggong Li Quanming is the pinnacle of regular script in Europe. Jiuchenggong's "Li Quan Ming" is meticulous and rigorous, without excessive expression, and is known as the "extreme principle of regular script". In other words, it is the starting point and end point of regular script research and a model for scholars of all ages.