What happened to the poetic style of the Eastern Jin, Southern and Northern Dynasties?

The characteristics of literature in Wei, Jin, Southern and Northern Dynasties: ① Great social changes in Wei, Jin and Southern and Northern Dynasties enriched the connotation of literature; The literature of this period has the characteristics of connecting the preceding with the following; (3) Poetry has completed the transition from four-character poetry, five-character poetry and Sao-style poetry to seven-character poetry, and a number of outstanding poets have emerged; 2. Jian 'an Literature ① During the Jian 'an period, poets represented by Cao and his son wrote poems based on what they saw, heard and experienced. History is called "Jian 'an Literature". ② The representative works of Jian 'an Literature include Cao Cao's Journey of Broken Limbs, RoyceWong's Poems of Seven Injuries and Cai Wenji's Poems of Mourning Anger. 3. Tao Yuanming and his pastoral poems. 1. Tao Yuanming, a poet in the Eastern Jin Dynasty, yearned for rural life, and wrote many pastoral poems with fresh and natural content and simple style in his life. Landscape poetry began to flourish. (2) Xie Lingyun's Climbing the Pool Upstairs is a masterpiece of landscape literature. (3) The representative work of Bao Zhao's contemporaries is It's Hard to Imitate, which has a great influence on later generations. 5. Folk songs of the Southern and Northern Dynasties. During the Southern and Northern Dynasties, a new kind of Yuefu poetry, namely folk songs, was popular for a while. (2) The representative works of southern folk songs include "Picking Sang Du" and so on. ③ The most famous northern folk songs are Chile Song and Mulan Ci. 5. vigorous art 1. The Formation and Development of Calligraphy Art ① At the end of the Eastern Han Dynasty, calligraphy became an art, and the famous scholar Cai Yong was a famous calligrapher at that time. (2) Zhong You of Cao Wei began to change the font from official script to regular script, which is a progress of China's calligraphy. His representative works include Preface to Lanting and Huang Tingjing. Her son, Wang Xianzhi, is also very accomplished in calligraphy, and he is called "Two Kings" with Wang Xizhi. (4) Wei Shuo, a female calligrapher in the Eastern Jin Dynasty, known as Mrs. Wei, learned her true story from Zhong You. Wang Xizhi studied calligraphy from Mrs. Wei. Wang Xizhi's wife Long Long is also a calligrapher.