“Chinesecitiesshouldcloseschools,cutworkinghoursandstop...
问题详情：“Chinesecitiesshouldcloseschools,cutworkinghoursandstopoutdooractivitiesduringthemostseriousperiodof1.________pollution，”theministryofenvironmentalprotectionhassaid.“Everypossiblenecessaryme...