The simulated questions are a little more difficult, but the real questions are different. It's hard and easy. It belongs to high volume.

Xuanwu, one of the four celestial spirits in ancient China mythology, also known as tortoise and snake, originated from the worship of stars in ancient times, which refers to dividing twenty-eight lodges into seven northern Xuanwu lodges according to the southeast and northwest of the four elephants. In the traditional culture of China, the four elephants refer to Qinglong, Baihu, Suzaku and Xuanwu, representing the east, west, north and south directions respectively.