One of the most dangerous accidents is catching fire. You should be careful with fires. People who are not careful sometimes cause fires that bum buildings and (11) . If you are ever in a burning building, crawl (爬) on the floor to the door and get out. The smoke and heat from the fire are in the (12) part of a room. The air near the floor is cooler and (13) . If your clothes get on fire, roll on the floor to (14) the air. With no air, the fire will go out. Firemen sometimes use water to (15) fires. The water cools the burning material so that the fire goes out.