Lemon is the most popular food for pregnant women because of its extremely sour taste, so it is called beneficial mother fruit or beneficial mother child. Lemon is rich in citric acid, so it is known as the "citric acid warehouse". Its fruit is juicy and crisp, with rich aromatic aroma. Because of its sour taste, it can only be used as a high-grade condiment to make drinks, dishes, cosmetics and medicines. In addition, lemon is rich in vitamin C, which can relieve phlegm and cough, promote fluid production and strengthen stomach. It is used for bronchitis, whooping cough, anorexia, vitamin deficiency, heatstroke, thirst and other symptoms. It is the killer of scurvy.