Airpollution,suchassmog,hasbecomeaseriousproblemaroundt...
問題詳情：Airpollution,suchassmog,hasbecomeaseriousproblemaroundtheworld.Besideswearingamask,whatelsecanwedotoprotectourselvesfromthedirtyair? Scientistshavedevelopedanewinhaler(吸入劑)thatcanreduc...