What is a back bow evil spirit? See more?

Dear, this is explained by modern science as the reason of centrifugal force. The tension of bow and evil makes residential feng shui very unstable; If you are on the back of the "bow" of the river, the foundation of the house is unstable; In modern cities, it is very common to have a "arched back" road, so we often see houses with rounded corners at intersections or corners. Ask for adoption!