2015年12月英语四级阅读真题练习及答案1思维导图
It is hard to track the blue whale, the ocean’s largest creature, which has almost been killed off by commercial whaling and is now listed as an endangered species. Attaching rad
树图思维导图提供 2015年12月英语四级阅读真题练习及答案1 在线思维导图免费制作，点击“编辑”按钮，可对 2015年12月英语四级阅读真题练习及答案1 进行在线思维导图编辑，本思维导图属于思维导图模板主题，文件编号是：b93875983f4b42d6ca2bcab34ea4c9b1
思维导图大纲
2015年12月英语四级阅读真题练习及答案1思维导图模板大纲
Itishardtotrackthebluewhale,theocean’slargestcreature,whichhasalmostbeenkilledoffbycommercialwhalingandisnowlistedasanendangeredspecies.Attachingradiodevicestoitisdifficult,andvisualsightingsaretoounreliabletogiverealinsightintoitsbehavior.
Sobiologistsweredelightedearlythisyearwhen,withthehelpoftheNavy,theywereabletotrackaparticularbluewhalefor43days,monitoringitssounds.ThiswaspossiblebecauseoftheNavy’sformerlytop-secretsystemofunderwaterlisteningdevicesspanningtheoceans.
TrackingwhalesisbutoneexampleofanexcitingnewworldjustopeningtocivilianscientistsafterthecoldwarastheNavystartstoshareandpartlyuncoveritsglobalnetworkofunderwaterlisteningsystembuiltoverthedecadestotracktheshipsofpotentialenemies.
Earthscientistsannouncedatanewsconferencerecentlythattheyhadusedthesystemforcloselymonitoringadeep-seavolcaniceruption(爆发)forthefirsttimeandthattheyplansimilarstudies.
Otherscientistshaveproposedtousethenetworkfortrackingoceancurrentsandmeasuringchangesinoceanandglobaltemperatures.
Thespeedofsoundinwaterisroughlyonemileasecond—slowerthanthroughlandbutfasterthanthroughair.Whatismostimportant,differentlayersofoceanwatercanactaschannelsforsounds,focusingtheminthesamewayastethoscope(听诊器)doeswhenitcarriesfaintnoisesfromapatient’schesttoadoctor’sear.Thisfocusingisthemainreasonthatevenrelativelyweaksoundsintheocean,especiallylow-frequencyones,canoftentravelthousandsofmiles.
1.Thepassageischieflyabout________.
A)anefforttoprotectanendangeredmarinespecies
B)thecivilianuseofamilitarydetectionsystem
C)theexposureofaU.S.Navytop-secretweapon
D)anewwaytolookintothebehaviorofbluewhales
2.Theunderwaterlisteningsystemwasoriginallydesigned________.
A)totraceandlocateenemyvessels
B)tomonitordeep-seavolcaniceruptions
C)tostudythemovementofoceancurrents
D)toreplacetheglobalradiocommunicationsnetwork
3.Thedeep-sealisteningsystemmakesuseof________.
A)thesophisticatedtechnologyoffocusingsoundsunderwater
B)thecapabilityofsoundtotravelathighspeed
C)theuniquepropertyoflayersofoceanwaterintransmittingsound
D)low-frequencysoundstravelingacrossdifferentlayersofwater
4.Itcanbeinferredfromthepassagethat________.
A)newradiodevicesshouldbedevelopedfortrackingtheendangeredbluewhales
B)bluewhalesarenolongerendangeredwiththeuseofthenewlisteningsystem
C)opinionsdifferastowhethercivilianscientistsshouldbeallowedtousemilitarytechnology
D)militarytechnologyhasgreatpotentialincivilianuse
5.WhichofthefollowingistrueabouttheU.S.Navyunderwaterlisteningnetwork?
A)Itisnowpartlyaccessibletocivilianscientists.
B)Ithasbeenreplacedbyamoreadvancedsystem.
C)Itbecameuselesstothemilitaryafterthecoldwar.
D)Itisindispensableinprotectingendangeredspecies
参考答案
1.B2.A3.C4.D5.A
相关思维导图模板
树图思维导图提供 广播电视奖项及评奖标准 在线思维导图免费制作，点击“编辑”按钮，可对 广播电视奖项及评奖标准 进行在线思维导图编辑，本思维导图属于思维导图模板主题，文件编号是：a4210651fa3a78355ac9f5101bb2c616
树图思维导图提供 1113爆卡会总结会会议纪要 在线思维导图免费制作，点击“编辑”按钮，可对 1113爆卡会总结会会议纪要 进行在线思维导图编辑，本思维导图属于思维导图模板主题，文件编号是：aaf6c152a765d5821e8e1787f2b3226e
沪公网安备 31011502019485号
上海工商