How did poetry evolve?

From the genre of elegant ode in the Spring and Autumn Period to the form of long and short sentences in the Han Dynasty, the representative works are Liu Bang's Song of the Wind and Cao Cao's Out of Xiamen-Toward the East Jieshi. In the Tang Dynasty, metrical poems and quatrains appeared with neat format and rigorous rhythm. This period is the peak of classical poetry. The limitation of form inspired the creator's wisdom and passion, and a large number of great works reached their peak in content and melody. Until the Song Dynasty, there was a popular era with various forms of words, which gave poets a relatively loose choice in form. Therefore, the Song Dynasty is another peak of classical poetry. In Yuan Dynasty, Qu became a popular pastime, so poetry gained great popularity in the form of Qu. At this stage, the poet pays more attention to the expression of content, and the form is completely open, which is closer to the modern formal structure. During the Ming and Qing Dynasties, due to cultural isolation, classical poetry entered a relatively depressed period.