But we do also have more complex systems that are used for space heatingand they fall into two categories: passive and active heating systems. Passive systems take advantage of the location or design of a house.

但我们也有更复杂的系统用于空间供暖，它们分为两类：被动加热系统和主动加热系统。无源系统利用房屋的位置或设计。