..and they are changing faster than ever before in human history. 而且正以人类历史上前所未有的速度变化
human encroachment is changing even the highest summits. 人类的侵犯甚至影响到顶峰的环境状况
the deciduous forests are changing. 可以看到落叶林在不断变化
The relentless power of the wind ensures that the face of a desert is continually changing. 风的无情力量总是使沙漠的面貌不断改变