Except for the metal futures varieties, which are elemental symbols, the other varieties are abbreviated in English or customized by the exchange according to the convention (for example, Dalian Soybean 1 is A, and Soybean No.2 is B). Most of them take the first two letters of English words, or a phrase composed of two English words each takes an initial letter to form a code, and some take the first and last letters of English words.