论文部分内容阅读
你知道什么叫“温室效应”吗?它对地球又有什么样的影响呢?A greenhouse is a building m ade of glass which is used for keepingoolplants warm when the outside tem perature is low.In a sim ilar w ay thereare several gases in the atm osphere w hich trap the heat produced by thesun and pre