Grain nourishes all things and rain moistens the sky. This means that food can nourish all things and rain can moisten the world. "Grain nourishes all things, rain moistens the sky" is an ancient saying from "Shangshu", which means "grain can nourish all things, and rain can moisten the world." This sentence emphasizes the importance of food and water to humans and nature, and is also an expression of the idea of ??"harmony between nature and man" in traditional Chinese culture.