1. Poetry is a literary genre that expounds ideas. "Poet, feeling the situation, expressing the heart, expressing emotion" and "preface to 300 poems without complaint".
Secondly, China's ancient poems can be divided into three categories: classical poems, regular poems and quatrains, and Yuefu is attached to these three categories. Du Fu's poems compiled by Guo Zhida in Song Dynasty can be simply divided into two categories: ancient poems and modern poems. Together with Yuefu poems, they are three categories of ancient poems.
Thirdly, the editor of Three Hundred Poems of Tang Dynasty divides poems into three categories: classical poems, regular poems and quatrains, and Yuefu is attached to these three categories. Ancient poems, regular poems and quatrains are divided into five-character regular poems, seven-character regular poems, five-character quatrains and seven-character quatrains. This is a kind of division. The classification of Shen Deqian's Poems on Tang Poetry is slightly different: he did not separate Yuefu, but added the category of five-character poems.
Fourth, ancient poetry is also called "ancient poetry" and "ancient style". Ancient poetry is written according to the style of ancient poetry. The name of poetic style is the general name of all kinds of poetic styles except Chu Ci before the formation of modern poetry. In the eyes of the Tang people, everything from the Book of Songs to Yu Xin in the Southern and Northern Dynasties is ancient. Therefore, there is no certain standard for the so-called ancient poetry style.
Fifth, quatrains are also called "cutting sentences". Sonnets may or may not be antagonistic, but they must be antagonistic to each other. Both quatrains and quatrains require even numbers. A metrical poem with more than eight sentences is called arrangement.