For example, one graphic illustration to which children might readily relate is the estimate that rainforests are being destroyed at a rate equivalent to one thousand football fields every forty minutes - about the duration of a normal classroom period.

例如，孩子们可能容易联想到的一个图解是，估计热带雨林正在以相当于每四十分钟一千个足球场的速度被破坏——大约是正常课堂时间的持续时间。