最佳答案:The environment is seriously under threat and it is our responsibility to live a
最佳答案:greener sky还可以,或fresher air第一句话有语法错误,在really前加个which第二段第一句也错了,是the heavy smog af
最佳答案:第四行which lasted for about three weeks 更好,后面可以加一句we must take actions tofight for