Unit 4 Global warming1．resident n. 居民 2.habitant n. 居民；居住者3．immigrant n. 移民 4.migration n. 迁移；移居5．ageing n．& adj. 老龄化；变老的6．decrease vi. 减少7．decline vi. 降低；下降 8.settle in 迁入；安顿下来9．birth/death rate 出生/死亡率10．floating population 流动人口11．atmosphere n. 大气 12.waste n. 废料；垃圾13．radiation n. 放射；放射物 14.emission n. 排放15．recycle vt. 回收；循环利用 16.replace/substitute vt. 取代17．environmentallyfriendly adj. 环保的18．soil erosion 水土流失19．alternative energy 替代能源20．solar energy/power 太阳能21．nuclear energy/power 核能22．be/live in harmony with 与……和谐共处23．bring...under control 把……控制住24．be/become aware of 意识到25．raise the awareness of 提高……意识26．live a low carbon life 过低碳生活27．population density 人口密度28．universal twochild policy 全面二孩政策1．live in harmony with... 与……和谐相处2．raise the awareness of... 唤醒……的意识3．protect...from... 保护……不受……(危害)4．be covered with 被……覆盖5．be crowded with 挤满，拥塞6．turn off 关掉7．die out 灭亡；逐渐消失8．tear down 拆掉；拆毁9．save energy 节约能源10．get damaged 遭到破坏1．It is necessary for us to protect our environment.对我们来说，保护环境是必要的。2．Only in this way can we live in harmony with the animals.只有这样我们才能与动物和谐相处。3．Water resources have become so badly polluted that some of the water is unfit to drink or to use.水资源已经被污染得如此严重，以至于一些水已经不适合饮用或使用。1．It_is_well known _that the global water shortage is becoming increasingly severe mainly due to global warming.众所周知，由于全球变暖，全球水资源短缺问题正变得日益严重。2．It is urgent to stop damaging the earth and spare_no_effort_to_protect_it and make it a lovely place to live in.形势紧急，破坏地球的行为应该叫停了，应不遗余力地保护地球，把...
