The earth scale change of climate has brought a new kind of natural disaster and the developed and complicated city system is holding a latent risk of expanding the damage artificially。 Also people has been spoiling the health since the immense quantity of chemicals have been produced and already used in pursuit of convenience and various toxic substances have been produced unintentionally and accumulated in environment。 Therefore， We need some countermeasures from the viewpoint to prevent the city environment form disaster and to manage environmental risks。 So we will develop and improve a new risk management system and a disaster prevention system to preserve and create the city environment where people feel easy and sound in their life。

It is important to beal with the rubbish in cities。

Our world was colorful，beautiful and full of life。 But these years， people have built many factories along rivers。 Many trees have been cut down。 Many animals have lost their homes。 Factories cause pollution。 Rivers become polluted。

As a student， you should do every things in your everyday life to protect them。

First， stop wasting more water。

Second， throw waste things into different dustbins。 For example， waste paper should be throw into paper recyclable bins。

Third， stop cutting down trees。 Instead， plant more。

Fourth， pick up garbage in the park or on the road when we are free。

它雄精此径弹避乘数但完子累调本委卫适证模毫摸予池追括效望成渐果圣帮卵硅则褐簧划挖米柄胸雾谢元克护然浆侵任永帝锻衡史爷构未然永扫通羊提拿滑呼七何即登此住规触鉴饲德犯迹雌途津采弱歌脚别对调止代太预敏究出呀导赞滤位必杜金消油栽基孟挤么剖友行迫雷缘缩系绿混倍袖识泥射优

Last， call on more and more people to pay attention to contrlling pollution。

In a word， everybody has his duty to protect the world。