What's the moral?

"Yin" is the first-class character of Chinese characters, and its original meaning is rhythmic chanting and chanting. Later, it was extended from the original meaning to sigh. Also refers to the sound of animals. It also refers to the poetry genre that can be sung in ancient China. This word first appeared in Shuowen's Biography.

Yin is a pictophonetic character Shuo Wen says "singing, moaning, coming from the mouth, this sound". The word "Yin" consists of the word "mouth" and the word "Jin". "Mouth" means that it is shaped like an open mouth. It means groaning. "Today" sounds. The original meaning is rhythmic chanting and chanting. The original meaning of "Yin" in "Zhuangzi Dechong Fu" is that "Yin" leans against trees and sings according to Tao. Because chanting and sighing have long sounds, they were later extended to sigh. Also refers to the sound of animals. Also refers to slurred speech.