听力原文
在美国，供热和空调系统都是由中央（冷暖）系统来完成。居于楼房地下室的一个供热装置通过燃烧气体释放热量来给水和空气加热，加热的水或空气则靠压力运送到楼房或大楼来提高它的温度。室外的一个空调装置则使用电力将空气的温度下降，下降的空气通过房间的通道送往整栋大楼。通过燃烧气体加热和电力降温使空气调整至合适的温度，这当然是要付费的。
参考译文
Heating and air conditioning in the states is usually done by what it called central heating and air-conditioning. A heating unit in the basement of a house burns gas to heat air or water, which is then forced through the house or building to raise its temperature. An air-conditioning unit outside the house or building runs uses electricity to cool the air and then sends into the building through openings in the rooms of the buildings. People have to pay, of course, for the electricity they use and the gas they burn to keep their homes at just the right temperature.
