Lu Xun once called this kind of labor chant shouting "Hang Yu Hang Yu" the earliest poetry, and humorously said that this is the "Hang Yu Hang Yu" school. The annotation of "Gongyang Zhuan·Xuan Gong Fifteenth Year" puts forward the view that "the hungry sing about their food, and the laborers sing about their work", which expresses the origin of poetry and the connection between labor in a very simple way.