I gave John a present but he gave me nothing （）. A: inreturn B: inturn C: inhand D: invain

中国大学MOOC:NobodyreallyknowshowbigLagosis.Whatsindisputableisthatitsgrowingveryquickly.Betweennowand2050,theurbanpopulationofAfricacouldtriple.Yetcitiesinsub-SaharanAfricaarenotgettingricherthewaycitiesintherestoftheworldhave.MosturbanAfricansliveinslums（贫民窟）;migrantsareoftennotmuchbetteroffthantheywereinthecountryside.Why?Theimmediateproblemispoverty.MostofAfricaisurbanisingatalowerlevelofincomethanotherregionsoftheworlddid.Thatmeansthereslittlemoneyaroundforinvestmentthatwouldmakecitiesliveableandmoreproductive.Withoutupgradesandnewcapacity,bridges,roadsandpowersystemsareunabletocopewithexpandingpopulations.WiththeexceptionofSouthAfrica,theonlylightrailmetrosysteminsub-SaharanAfricaisinAddisAbaba,Ethiopia.Trafficjamleadstoexpenseandunpredictability,thingsthatkeepinvestorsaway.Inotherpartsoftheworld,increasingagriculturalproductivityandindustrialisationwenttogether.Moreproductivefarmersmeanttherewasasurplusthatcouldfeedcities;inturn,thatcreatedapooloflabourforfactories.ButAfricancitiesaredifferent.Theyaretoooftenbuiltaroundconsumingnaturalresources.Governmentisconcentratedincapitals,soisthemoney.MosturbanAfricansworkforasmallminorityoftherich,whotendtobeinvolvedineithercronyish（有裙带关系的）businessesorpolitics.SinceAfricanagricultureisstillbroadlyunproductive,foodisimported,consumingaportionofrevenue.Sowhatcanbedone?ThoughAfricancountriesarepoor,notallAfricancitiesare.InLagos,foreignoilworkerscanpayasmuchas65,000dollarsperyearinrentforamodestapartmentinasafepartoftown.Ifthatincomewerebettertaxed,itmightprovidetherevenueforbetterinfrastructure.Ifcityleadersweremoreaccountabletotheirresidents,theymightfavourprojectsdesignedtohelpthemmore.Yetevenasnewroadsarebuilt,newpeoplearrive.Whenacityspopulationgrowsby5%ayear,itisdifficulttokeepup.46.Whatdowelearnfromthepassageaboutcitiesinsub-SaharanAfrica?A.Theyhavemoreslumsthanothercitiesintheworld.B.Theyaregrowingfastwithoutbecomingricher.C.Theyareasmodernisedasmanycitieselsewhere.D.Theyattractmigrantswhowanttobebetteroff.47.Whatdoestheauthorimplyabouturbanisationinotherpartsoftheworld?A.Itbenefitedfromthecontributionofimmigrants.B.Itstartedwhenpeoplesincomewasrelativelyhigh.C.Itbenefitedfromtheacceleratedriseinproductivity.D.Itstartedwiththeimprovementofpeopledlivelihood.48.Whyissub-SaharanAfricaunappealingtoinvestors?A.Itlacksadequatetransportfacilities.B.Thelivingexpensestherearetoohigh.C.Itisonthewholetoodenselypopulated.D.Thelocalgovernmentsarecorrupted.49.InwhatwaydoestheauthorsayAfricancitiesaredifferent?A.Theyhaveattractedhugenumbersoffarmlabourers.B.Theystillrelyheavilyonagriculturalproductivity.C.Theyhavedevelopedattheexpenseofnature.D.Theydependfarmoreonforeigninvestment.50.WhatmightbeasolutiontotheproblemsfacingAfricancities?A.Loweringofapartmentrent.B.Bettereducationforresidents.C.Morerationaloverallplanning.D.Amoreresponsiblegovernment.

ThelessonsofstatefailureTraditionaldiplomacydealswithrisksofconflictbetweennation-states.Theserisksareofcoursestillpresent,butamorepervasivedangeristhatstateswillsimplycollapse.OfadozenorsoconflictsinAfricainrecentyears,few,ifany,haveinvolvedcross-borderaggression.Instead,bankruptandimpoverishedstateshaveimploded,thevacuumfillednotbyregimeswithnewlyconsolidatedpowerbutbybrutalviolenceengulfingcivilians.Thedisasterthenfansouttoneighboringcountries,andeventuallymuchfartherafield.Aspecial"taskforceonstatefailure"setupbyAmerica’’sCIAhasfoundthatthreevariablesaremostpredictiveofstatestabilityorinstability:theopennessoftheeconomy;democracy;andinfantmortality.Insub-SaharanAfrica,wheremuchofthepopulationlivesontheedgeofsubsistence,povertyandsloweconomicgrowth,oroutrightdecline,increasedthelikelihoodoffuturestatecollapse,therebytrappingthecountriesinaviciouscircleofpovertyandpoliticalinstability.Richcountries,ontheotherhand,tendtomaintainpoliticalstabilitywhich,inturn,promotesfurthereconomicdevelopment.Whencountrieswereclassifiedin1990bytheirstatusintheUnitedNationsHumanDevelopmentIndex(anindexofincome,literacyandhealth),high-developmentcountriesachievedrobustandstableeconomicgrowthduring1990-98,withaveragegrowthratesofaround2.3%ayearandwith35outof36countriesenjoyingrisinglivingstandards.Middle-developmentcountriesachievedaslightlylowergrowthrate,1.9%ayear,but7outof34countriesexperiencedoutrightdeclinesinlivingstandards.Thepoorestcountriesaveragednoeconomicgrowthatall,with15outof39experiencingfallinglivingstandards.Theflip-sidetothepovertytrap,however,isthatthegainsofdevelopmenttendtobesustained,oncecountriesbreakthroughtosufficientlevelsofincome,healthandliteracy.ConservativesinAmericaoftenaskwhyitmattersifanimpoverishedcountrycollapses.Theansweristhat,asidefromhumanitarianconcerns,crisesinsuchfarawayplacesoftensucktheUnitedStatesintocrisisaswell.Since1960,AmericahasbeendraggedintomilitaryconflictsinCuba,Thailand,Laos,Congo,Vietnam,theDominicanRepublic,Cambodia,Cyprus,Lebanon,Zaire,ElSalvador,Libya,Lebanon,Honduras,Nicaragua,Chad,Liberia,Bosnia,Somaliaand,morerecently,KosovoandColombia.Statefailures,orevenmilderstateinstability,havealsounderminedAmericanandglobalintereststhroughgloballytransmittedfinancialcrises,drug-trafficking,money-laundering,terrorism,thespreadofdiseasessuchasAIDSandmassrefugeeflows.Onthepositiveside,sustainedeconomicdevelopmentwouldcreatenewandpotentiallylargegainsfromtrade,aswellasmuch-neededcooperationinscienceandculture.Evenwhenaproblemiscorrectlyidentified,thereisastunningdisconnectbetweenriskandactioninAmerica’’sforeigneconomicpolicy.TheglobalAIDSepidemic,forexample,hasrecentlyandwiselybeenidentifiedasarisktothesecurityoftheUnitedStates.WhatactionhasbeentakenPresidentGeorgeBushhascalleduponAmericanstogivejust$200million,or70centseach,tothenewglobalfundtofightthedisease.Thefailuretomakeevenbasicinvestmentsinforeignpolicyhasbeenpervasive,andtheexamplesarelegion.Elevenyearsago,thelastprimeministerofunifiedYugoslavia,AnteMarkovic,launchedalast-ditchplanforeconomicstabilization.HeappealedtoEuropeandtheUnitedStatesforareductionindebt-servicingandothermodestfinancialsupport,butwasturneddownbythecreditorgovernments.Economicstabilisationwasundermined,andthishelpedSlobodanMilosovictogettheupperhand.Therest,astheysay,ishistory.InthepasttwoyearsAmericaandEuropeancountrieshavemadethesamemistakeinNigeria,animpoverishedandunstablecountryemergingfromyearsofcorruptdespotism.AlthoughNigeria’’soilearnings,netofproductioncostsandincometoforeignoilcompanies,amounttoaroundonly$90perNigerianayear,theUnitedStatesandEuropecontinuetoprevaricateoverurgentlyneededdebt-reductionbecausetheoilearningsareeasytosqueezefordebt-servicepayments.ThenewdemocraticregimeofPresidentOlesegunObasanjoisputatrisk,andLibya’’sleader,MuammarQaddafi,doesnotmissachancetoinflamemattersinNigeria’’sIslamicnorthernstates.Areaafterareaofneglectcanbecatalogued,fromthestrife-tornAndestoregionsaroundtheworldunderminedbyclimatechange.Throughallofit,theUnitedStatesbarelyliftsafinger.ItsomehowthinksthatsendingtheimpoverishedandunstablegovernmentsdownPennsylvaniaAvenuetogetloansfromtheIMFandtheWorldBankwilldothejob,butevensomestaffofthoseorganisationsnowpubliclyacknowledgethattheyhavefailed:makingloanswhengrantsareneeded,imposingexcessiveausteritybycollectingratherthancancelingdebts,andfailingtofindpartner-institutionswiththescientificexpertisetotackleunderlyingproblemsofdisease,lowfoodproduction,climaticstressandenvironmentaldegradation.

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