First of all, this is a poem that praises traditional virtues. The original sentence is "The sharp edge of the sword comes from sharpening, and the fragrance of plum blossoms comes from the bitter cold." It comes from "Warning to the World and the Sage: Diligent Chapter", which means: the sharpness of the sword. The edge of the blade comes from constant sharpening, and the fragrance of plum blossoms comes from the cold winter. It means that if you want to have precious qualities or beautiful talents, you need continuous efforts, practice, and overcoming certain difficulties to achieve it.
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