精选优质文档-倾情为你奉上Nowadays, more and more people realize its necessary and important to protect the environment. Also,there are some people who dont pay attention to hygiene and they cant stop littering the rubbish casually or spitting everywhere all the time.And in addition, there are a few factories often cutting down the trees, discharging chemicals and dirty water and so on.And it causes many problems like the Greenhouse Effect.If they do these day by day and our life will be harder and