What do you mean by "the gate is dry" in the gossip?

Mao means due east, unitary means due west, and Maoshan means that the house sits east and west, so in order to avoid the dead door in the southwest, only the northwest door or courtyard door can be opened. Gossip has no doors, only two doors are dry! It's interesting to do things. Most people don't dare to use the dry door easily. Most governments and city gates use it!