1. This refers to the unique style of Yan Zhenqing's calligraphy. Song Zhao's "Xuan He Shu Pu Yan Zhenqing": "Only loyal to heaven knows the world, so the spirit is found in the book case, unique and eclectic ... The latter folklore is to seek the end of its shape, called the silkworm head swallow tail, and get it; I just know the beauty of painting sand with a cone, and people with good hearts can't destroy it. " Later, "Silkworm-headed Swallowtail" was generally used to refer to a sick pen that was not good at studying the inscriptions on the face. Mi Songfei's "Famous Sentences of Haiyue": "There is no phoenix-tailed pen in the original work, which is similar to Guo Zhiyun's" Competing for Seats ".
2. Describe calligraphy as dignified and light.
3. To make a metaphor, Li Shu draws the pen sideways and closes it sideways. A long painting starts with a pen, and the back front rises like a silkworm head; When the shear wave receives the pen, the pen tilts upward and is shaped like a goose's tail.