The gate is the air port, the only place where the air flows inside and outside, and the throat and barrier to contact with the outside world. This depends on the environment, region, atmospheric circulation and other factors. In the geomantic omen of Yangzhai, the door occupies a very important position. For example: whether the door direction accepts the big mysterious sub-line; Whether the door position gets seasonal auspicious stars and so on.
Three essentials: door, main room and stove.
Six things: doors, roads, stoves, wells, pits and toilets.
Four choices: 1 Qiansu Zaku (South Gate) 2 Zuo Qinglong 3 You Bai Hu 4 Hou Xuanwu (North Gate)
The door should match the road shape: Xuanwu Shuibei