Hieroglyphic of “Hua” was originally derived from “two people standing together with one is head-stood”, imitating performers’ movement in an acrobat with the two radicals. It means "change”, and also the process of things from birth to death, from rise to fall.
The earliest structure of “Xue” in Oracle was like “two hands holding a learning hall”, meaning the extreme dedication to learning. Most primitive meaning of this character was the initialtive education of children, while slowly after it extended the meaning of “discussing with each other, imitation, and transferring knowledges”.
The structure of “Zhi” in hieroglyphics imitates two radicals with a tree on the left and the felling tool on right, meaning straight forward that you can cut down a tree once it’s grown up for woodwork. Gradually the character derived to present the meaning of “production and manufacture”.
The original hieroglyphic meaning of “Pin" is super simple and direct. It is a combination of three vessels, which is used to directly express the meaning of "numerous". When time passes by, the new meaning as the “category” and “quality” of things have been extended.