Thepersistenthazeovermanyofourcitiesisareminderofthepollutedairthatwebreathe. Over 80% oftheworld'surbanpopulationisbreathingairthatfailstomeetWorldHealthOrganisationguidelines, andanestimated 4.5 millionpeopledied __26__ fromoutdoorairpollutionin 2015.
Globally, urbanpopulationsareexpectedtodoubleinthenext 40 years, andanextra 2 billionpeoplewillneednewplacestolive, aswellasservicesandwaystomovearoundtheircities. Whatismoreimportant, thedecisionsthatwemakenowaboutthedesignofourcitieswill __27__ theeverydaylivesandhealthofthecominggenerations. Sowhatwouldasmug-free, oratleastlow-pollution, citybelike?
Traffichasbecome __28__ withairpollution, andmanycountriesintendtobanthesaleofnewpetrolanddieselcarsinthenexttwodecades. Butsimply __29__ toelectriccanwillnotmeanpollution-freecities. Thelevelofemissionstheycausewilldependonhowtheelectricitytorunthemis __30__, whilebrakes, tyresandtoadsallcreatetinyairborne __31__ astheywearout.
Acrossthedevelopedworld, earuseisindeclineasmorepeoplemovetocitycenters, whileyoungpeopleespeciallyare __32__ forothermeansoftravel. Researchersarealreadyaskingifmotorvehicleusehasreachedits __33__ andwilldecline, buttransportplannershaveyettocatchupwiththis __34__, insteadoflayingnewroadstotackletrafficjams. AsusersofLondon'sorbitalM25 motorwaywillknow, newroadsrapidlyfillwithmoretraffic. IntheUS, studieshaveshownthatdoublingthesizeofaroadcan __35__ doublethetraffic, takingusbacktothestartingpoint.
A) altemate
B) crown
C) determine
D) generated
E) locating
F) merged
G) miniatures
H) opting
I) particles
J) peak
K) prematurely
L) simply
M) swiching
N) synonymous
O) trend