Thefirstdecadeofthe21stcenturyhasbeenaremarkableperiodforinventions．Herearesomeofthemostinfluentialinventionsinthefirstdecade．1．iPodandiTunes：ThesetwoinventionsfromAppleInc．presentedarevolutionarynewwayfo
Thefirstdecadeofthe21stcenturyhasbeenaremarkableperiodforinventions．Herearesomeofthemostinfluentialinventionsinthefirstdecade．
1．iPodandiTunes：
ThesetwoinventionsfromAppleInc．presentedarevolutionarynewwayforpeopletolistentomusicandfundamentallychangedtherecordingindustry．iTuneswasintroducedinJanuary，2001andwasmarketedasaprogramthattransferred （转录） CDsintodigitalaudiofilesandhelpedorganizedigitalrecordings．Laterthatyear，AppleintroducedtheiPod，adevice （设备）thatusedaharddisktostoremusicfiles．Thefirstmodelhada5GBcapacityandcouldholdover1，000songs．
2．iPhone：
TheiPhonefromAppleInc．wasreleasedinJuneof2007andcompletelychangedthewaymobilephonesareusedpersonallyandinbusiness．Olderphonestypicallyincludedvoicecommunicationsandsometimesakeyboardtosendtextmessages．Phonesthatofferedinternetaccesswereusuallyunreadableanddifficulttohandle．TheiPhoneintroducedthemulti-touchinterface（界面） thatallowsforquickandeasyaccesstodata，music，andpictureswhileprovidingstorageforotherimportantinformation．
3．ElectricCar：
TeslaMotorswasformedin2003．Itwasthefirstcompanytoproduceavehiclethatdidnothavesignificantdifficultyinproductionorsales．Teslavehiclesclaiman88% efficiencyratingcomparedto20-25% fortraditionalgasoline-poweredcars．AccordingtodatafromtheNationalFireProtectionAssociation，adriveris"5timesmorelikelytoexperienceafireinatraditional gasolinecarthanaTesla．"
4．Facebook：
Facebookwasnotthefirstsocialnetworkingwebsite，butsinceitsintroductionin2004ithasbeenthemostinfluentialmedium.150millionusersworldwideappreciateitsmultitudeoffeaturesandeasyaccessibility．Theconceptofbuildingconnectionsthroughinternethaschangedthemannerinwhichbusinessesmarkettheirproductsandpeopleinteractwithoneanother．
21．WhatcanwelearnaboutiTunes？___
A．Itisusedtostoremusic．
B．Ithasaharddisk．
C．ItturnsCDsintodigitalaudiofiles．
D．ItwasintroducedafteriPodwasinvented．
22．Comparedtoatraditionalga