Yellow water kills yellow water and saves poor yellow water. Specifically:
Geng Dingkun went to the grave, and B and C had to be flooded first. A Gui was worried that seeing the root lies in the heart, so he was afraid to do it as a new waterway.
It means standing upright, water flowing out of Kun, committing necromancy, and so on. But there are:
Xin entered the palace of millions of villages, Gui returned to the land of articles, B flowed to the rich, and Ding Kun was always fragrant. This mainly depends on the specific environment and the direction and mode of water flow. It's a long story here