Wuhan，thecapitalcityofHubeiprovince，hasissuedsmogwarningsforthreedayssinceMondaybecauseofseriousairpollution．Thelingeringsmogforcedconstructionsitestostopworkandprimaryandmiddleschoolstosuspendoutdooractivitie
Wuhan，thecapitalcityofHubeiprovince，hasissuedsmogwarningsforthreedayssinceMondaybecauseofseriousairpollution．
Thelingeringsmogforcedconstructionsitestostopworkandprimaryandmiddleschoolstosuspendoutdooractivities．FromMondaythroughWednesday，thecity'sairqualityindexreadingremainedhigh，withthehighestreadingat323，withPM2.5，orparticulatemattersmallerthan2.5microns，asthemainpollutant，accordingtothecity'smeteorologicalbureau．Anyreadingover300isconsidered"seriouslypolluted"．
ThecityexperiencedatleasteightheavilypolluteddaysinthefirsttwoweeksofDecember，withtheairqualityindexreadingreachingahighof440，ChinaNewsServicereported．
AmongthoseaffectedwasasquaredancingteaminJiang'andistrict，whichhadtostopdailypracticesafterseveralmembersfellill．Squaredancingisacommonopen-airfitnesspracticeacrossChina，withmostoftheparticipantsmiddle-agedorelderlywomen．
MediareportedtheleaderofonedancingteamhadtogotoahospitalaftershehadanasthmaattackonDec11．
IdentifiedonlyasFang，65，thedanceteamleadersaidshedecidedtosuspendthepracticesaftershelearnedherillnesswascausedbysmog，andafterseveralothermembersalsofellill，thereportsaid．
Thecityplanstoinvest28billionyuan（$4.61billion）inairpollutioncontrolby2017．Theplansaysthecitywillboostthedevelopmentofcleanenergyvehiclesforpublictransportationandremoveallofthecurrent140，000heavy-pollutingvehiclesfromWuhan'sroadsbytheendof2016．
67．What'sthemainideaofthepassage？___
A．Wuhandecidedtoremovemostconstructionsites．
B．Wuhanissuedsmogwarningsforthreedaysbecauseofsmog．
C．Thecityisreportedlyunfitforphysicaltraining．
D．Outdoorexercisecandecreasetheinfluenceofsmog．
68．Theairqualityindexreadingofthecityoncereachedtoanextremeof___．
A.300 B.323 C.440 D.140，000
69．Thecityauthoritieswillfirstlydevelop___inthefuture．
A．greentransportation
B．environmentallyfriendlyenergy
C．heavyvehicles
D．trans