Even when we turn off the bedside lamp and are fast asleep, electricity is working for us, driving our refrigerators, heating our water, or keeping our rooms air-conditioned.

• 参考译文：即使在我们关掉了床头灯深深地进入梦乡时，电仍在为我们工作：为电冰箱提供动力，把水加热，或使室内空调机继续运转。