In these two days, the sky is very blue, with shining sunshine and white clouds and the ocean is pretty clean, with dark blue sea and crystal-like foams. The sky, clouds, sea and waves joint effort, unfolding one amazing scene to us. Therefore, many pictures about that have been posted on Wechat (Weixin). Actually, that should be the real picture of the nature, but it has been the rare thing since this century. These pictures fast spread among friends demonstrate people's anxiety about the worse environment, which has been the national focus recent years. Definitely, bad environment is the cost, which human being must take for polluting the earth. To destroy the ecological balance doesn't need more effort, while to reverse the worsening situation and maintain it need's more generation's effort.