Original meaning: the nature, state or situation is different from before, changing. Such as: tone sandhi, change, change, change, change, change (slightly change the original method to meet the needs of the facts), strengthen, impermanence. The extended meaning of this word is very rich, because diaosi itself can be extended to relationship, and words can also be extended to oral commitment. The relationship between people is easy to change, so it can be said that verbal promises have not been fulfilled. Change is only an objective description, which can be good or bad. The relationship between two people can be changed from irrelevant to iron relationship, or from iron relationship to hostile relationship.