The word "xing" in The Book of Songs is interpreted by Zhu as "talking about other things first to arouse what is sung", that is, paving the way for what is sung with other things, which is often used at the beginning of a poem or a chapter. Sometimes when a sentence in a poem looks interesting, whether it is interesting can be judged by whether it is used at the beginning of a sentence or paragraph. For example, in Feng Wei's self-protection, "Mulberry leaves are flourishing before they fall" means prosperity. About the most primitive "xing" is just a beginning, which has nothing to do with the following, but shows drift and association for no reason. Besides, there are many meaningful uses of "Xing", such as metaphor, symbol and contrast. But it is precisely because "Xing" is originally produced by the drifting and association of ideas without reason, so even if it has a more real meaning, it is not so rigid, but subtle. Because "Xing" is such an implicit and freely used technique, poets who like the implicit and euphemistic charm of poetry in later generations are particularly interested in it. Their own clever tricks and innovations are numerous, which constitute the special taste of China's classical poetry.