回复：怎么处理 mold?

You first need to find out why moister built up in that area. It may because your dryers vent is clogged or not in right position, or heating vent is not insulated right (where old air meets hot air inside the house to cause moister).

Before you find the source, don't do anything. Otherwise you fix dry wall now, mold will come back in just a few months.

After you fix the source, minor mold can be cleaned. If mold is too wild spread, replace dry wall.