Old people who are so old have worse tolerance for cold and heat. It is good to turn on the air conditioner to adjust the appropriate indoor temperature, but it is good to ensure that the wind from the air conditioner does not directly blow the human body. Moreover, when the air conditioner is turned on, because the room is sealed, the air in the room will be dirty and the oxygen concentration will decrease for a long time. So it's best to open the doors and windows for air every once in a while.