The four-character poem stage represented by The Book of Songs is the initial stage of ancient poetry. Every sentence is four words, and every sentence rhymes.
Second, the miscellaneous language stage:
The transition from The Book of Songs to The Songs of the South is the transition from four words to miscellaneous words in China's ancient poetry. By adding the modal particle "xi" to each sentence, two three-sentence sentences are connected into a seven-sentence sentence, including some five-sentence sentences. This period is called the miscellaneous language period.
Third, Yuefu stage:
The forms of Yuefu poems in China began to appear in the Han Dynasty, mainly with miscellaneous words. However, the modal particle "Xi" is no longer used in poetry, and poetry is completely composed of three-word or five-word sentences. Representative works such as The Battle of the South and Evil.
Four-word or five-word stage
At the end of the Eastern Han Dynasty, complete five-character poems began to appear in ancient China. Each sentence of the whole poem consists of five words, which rhyme throughout. His representative works include Nineteen Ancient Poems and Peacock Flying Southeast.
Five-word or seven-word stage
After the maturity of five-character poetry, poetry began to develop into seven-character poetry. After the appearance of seven-character Yuefu poetry (that is, the whole poem consists of three words, five words or seven words), a new poetic style has gradually formed, that is, the whole poem consists of seven words, that is, seven words per sentence, and the rhyme of each sentence has become the rhyme of every other sentence. Ge Yanxing written by Cao Pi at the end of the Eastern Han Dynasty is the earliest seven-character poem so far.
During the Southern Dynasties, Shen Yue and others formulated the principle of "four tones and eight diseases" in poetic style, and since then the poetic style has become more standardized.
In the Sui Dynasty and the early Tang Dynasty, poetry was still dominated by five words. Starting from Wu Zetian, Shen Quanqi, Song and others began to create seven-character poems, and from then on, seven-character poems began to dominate the whole poetry world together with five-character poems. At this point, the poetic style developed completely and began to enter a glorious period.