It is said that many people praised Cao Cao's skillful calligraphy, and some of them said, "The calligraphy of the Prime Minister is unparalleled, but it is a pity that the word' Kun' is missing three points." Cao Cao laughed after listening to it, pointed to the river and praised it: "Is there no water?" There is much water in the river, so there is no need to gild the lily. "Everyone suddenly enlighted. Therefore, later generations compiled this story into a jingle: "Wild waves and huge waves flow along the stone, so you don't have to point to it next to the word' Yi'. "