What is a wave of clearing in Sangtian?

Sang's "clear wave" refers to the surging water waves in the rivers, describing the situation as turbulent. Sang Pan Tian Qing Bo is an idiom, which comes from a sentence in Du Mu's poem "Two Poems of Feeling Cold at the Fence Gate in Autumn Night": "It's hard to make waves when the sea changes." This poem depicts the scene of social change and political turmoil, and was later extended to describe the turbulent situation and the changing artistic conception of society.