-To evaluate calligraphy works, first of all, how to have a clear understanding of one's own calligraphy level, the historical knowledge of calligraphy, the development and evolution of Chinese characters, the characteristics, structure, pen, ink, composition and seal cutting knowledge of various calligraphy styles, etc. These are all prerequisites for commenting on calligraphy works, just like a ruler that uses weights and measures to weigh weight and length, so as to be fair and reasonable.