浙江大學2013年考博英語完形填空

Do you forget to turn off the lights and heaters when you go out of a room? In 2040 it will not matter. They will turn　themselves off and on again when you return. You will choose the temperatures for each room. The lighting and the humidity. A sensor will detect the presence of a human (and, with luck, ignore the dog!) and turn the systems on and when the humans leave it will turn them off again.