Why should poetry transition to ci? What is the root of a word?

Words are not the transition of poetry. However, in its own development process, it gradually moved closer to poetry and eventually fell into the same literary category.

Ci appeared in the Tang Dynasty. Due to the prosperity of cultural exchanges between the Tang Dynasty and the western regions, some "Hu Yue" from the western regions were introduced into the Central Plains, and combined with the music of the Central Plains, a form called "Quzi" was produced, which was sung while playing. Ci is lyrical, so it is called "Qu Zi Ci". Because the music is different, the format of words is different, and everything is filled in according to the "spectrum", so the basis of lyrics is "spectrum". Different tunes are called "epigrams".

The earliest lyrics are very popular and colloquial, similar to modern lyrics. Because most people who write lyrics are poets, the lyrics gradually move from "vulgarity" to "elegance". Later, the word spectrum began to break away from the score of "Zheng Yu in the Palace Corner", but was filled according to the rhyme. Because words belong to long and short sentences, they are more expressive than poems in lyricism, and they are loved by poets and readers, and become a literary genre that keeps pace with poems. Later, with the development of characters, they became more and more similar to poems in form (meter and rhyme), so people put them into a big category. ?