What is the connection between ancient poetry and music and dance?

Poetry is the oldest and most literary style, which comes from ancient labor songs (later developed into folk songs) and sacrificial eulogy. Poetry was originally a general term for poetry and songs. "Shangshu Yu Shu" records: "Poetry expresses ambition, song expresses Tao, sound is eternal, law and harmony." "Book of Rites and Music" records: "Poetry expresses ambition; Song, chanting its voice; Dance, move its capacity; The three are based on the heart, and then the instrument follows it. " In the early days, poetry, song, music and dance were integrated. Poetry is the lyrics. In actual performances, it is always sung with music and dance. Later, poetry, song, music and dance developed independently and became independent adults. Distinguish songs from poems by entering music or not. Music is a song, but poetry is not. Poetry is a kind of language art, which is differentiated from songs, and songs are a kind of music literature with a long history. The Book of Songs is sung with music. Technically, it is a song. Because of this, The Book of Songs is regarded by scholars as a symbol of the maturity of China's music literature.