What does a bad almanac mean?

In the Gregorian calendar, bad walls mean tearing down houses and walls.

Wall: 1, wall: city wall. 2, the city,: the provincial wall (provincial capital). Building a house needs a wall, so a bad wall means tearing down the house and scraping the wall.

"Hee Sa Flat House Book": Bad walls should be broken in the middle of the month; Avoid building the moon, earth buildings, robbing evil spirits, disasters, moon evil spirits, moon punishment, moon fatigue, earth symbols, earth capsules, and later using the earth king.