Why are there songs in poetry?

Long lines and short songs, drinking horses in the army, drinking horses in the Great Wall Cave, and singing songs in military vehicles shops.

Ballad-like Shuifu Songs and Farmers' Songs

Quote Li Ping from New XuanYueFu.

Qulei Xi Zhou District Yuanqu Ancient Xiang Si District

Lei Yin Fu Liang Yin Qin Yin Zhong sat and sang "Grow Old Together" in the evening.