Two-part allegorical saying of shit on the grave

Two-part allegorical saying is a special language form created by working people in China since ancient times. This is a short, interesting and vivid sentence. It consists of two parts: the former part plays the role of "introduction", like a riddle, and the latter part plays the role of "backing", like a riddle, which is very natural and appropriate.

For example: rolling pin blows fire-I don't know anything; Shuichong Longwang Temple-one family denies the other.