Why do you want to be AI Ai when Tomb-Sweeping Day arrives?

Before Tomb-Sweeping Day, the Hakka people in Guiling had the traditional custom of making "mourning". I once heard grandma say that fresh wormwood is an "evil". Tomb-Sweeping Day can "ward off evil spirits" by eating fresh wormwood and cold wormwood. Years of illness do not invade! Why eat cold food instead of hot food? Of course, there is a reason. Because the day before in Tomb-Sweeping Day is called Cold Food Festival, which is the day when people ban fire and sweep graves, and because Tomb-Sweeping Day is very close to the Cold Food Festival, gradually, the Cold Food Festival and Qingming Festival are integrated. The Cold Food Festival has become another name for Tomb-Sweeping Day and a custom in Tomb-Sweeping Day: Tomb-Sweeping Day only eats cold food without fireworks. It makes sense to say "ward off evil spirits", because wormwood itself is a kind of herbal medicine, which has the function of aromatherapy and dampness removal. For the Qingming Festival, it can really prevent infectious diseases such as colds!

Please accept it, thank you!