China's poetic style. Also known as broken sentences, broken sentences and broken poems. Each song has four sentences, usually five or seven words. Known as the five wonders, seven wonders, and occasionally six wonders. It originated from the ballads of the Han, Wei, Southern and Northern Dynasties. The name "Jueju" originated in the Southern Dynasties. Liang, generally, uses quatrains to refer to four short poems, and their rhymes are relatively free, or they are ancient quatrains. After the Tang Dynasty, quatrains in the near aspect prevailed, and the meter was the same as the first, last or middle four sentences in eight metrical poems. Therefore, some people in the Tang Dynasty attributed quatrains to metrical poems in their poetry collections. Later, some scholars thought that quatrains were formed by cutting off half of orthographic poems. Quatrains are flexible and light, suitable for expressing fleeting thoughts and feelings, and are widely used by poets, and their creation is more prosperous than other poems. In Song Dynasty, Hong Mai compiled 10,000 quatrains in Tang Dynasty, accounting for 1/5 of the total number of existing Tang poems. Besides Li Bai, Wang Changling, Du Mu and Li Shangyin are good at quatrains, there are many famous works throughout the ages, which are not necessarily written by famous writers. In addition, most quatrains in the Tang Dynasty were sung by music, such as Cheng Wei Qu by Wang Wei, Qing Ping Diao by Li Bai, Zhi Zhu Ci by Liu Yuxi and Bai Juyi, and Yang Liuzhi. Therefore, quatrains are also considered as Yuefu in the Tang Dynasty.