2017-2018学年高中英语必修三课后阅读作业: 十一 Module 3 Period 3 Grammar 语法专题课
Ⅰ. 阅读理解It was once thought that air pollution affected onlythe area immediately around large cities with factoriesand heavy automobile traffic. Today, we know thatalthough these are the areas with the worst air pollution,the problem is actually worldwide. On several occasions over the pastdecade,