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{{*HTML*}}??阅读下面这篇短文短文后列出7个句子请根据短文的内容对每个句子做出判断 ??????? ??????????? {{B}}HelpYourChildBecomeaReader{{/B}}??Encouragingearlyreading skillscanbuildapathtoalifelong终身的loveofreadingandcanhelpyour childgetaheadstartinschool.Whilereadingtoyourchildisstillthemost importantthingyoucandotobuildreadingskillstherearemanytechniques thatcanhelp.??Makereadingfun.Playgameswithyourchildas youread.Manytraditionalchildren’sgamescanbeadaptedtoencouragereading skills.??WhilereadingorduringplaytellyourchildIspy withmylittleeyesomethingthatbeginswiththeletterb.Helpthechild findsomethingonthepageorintheroomthatbeginswiththatletter.For example.Iseeabarn.Thiscanalsobeusedtoteachbeginninglettersounds. Ispywithmylittleeyesomethingthatbeginswiththesound‘s’.Helpthe childfindawordthatbeginswiththessound.??Inthis variationonthepopulargameinstructthechildthatSimonsays‘pointto somethingthatstartswiththelettern.’Thechildcanthenfindanobjectin theroomorabodypartsuchasthenosethatstartswiththeletter presented.Thiscanalsobeusedtoteachbeginningsounds.??Make agameoutofrhyming押韵wordsbymakingupsillywordstorhymewiththe child’snameoffavoritetoys.Thissetsthestageforrhymingrealwordsby showingthechildthesimilaritiesofsounds.Asthechildmastersmakingupthe wordsbeginrhymingrealwordstooneanother.??Tipstoraisea successfulreader:??Putbooksinplaceswherethechildplays.If booksareeasilyaccessiblechildrenaremorelikelytopickthemup.? ?Letchildrenreadtoyoubylookingatpictures.Makingupstoriestogo alongwithillustrationshelpschildrendiscoverhowwordsrelateto pictures.??Takebooksalongontripsorevenshortvisitstothe doctor’sofficeorgrocerystore.??Havechildrenhelpyoushop. Readinggrocerylistsandlookingforspecificitemshelpsbuildsight vocabulary.Youcanaskyourchildtotellstoriesbasedonpictures.
{{*HTML*}}{{B}}第三篇{{/B}} TooLittleforGlobalWarming? ?Oilandgaswillrunouttoofastfordoomsdayglobalwarmingscenariosto materializeaccordingtoacontroversialnewanalysispresentedthisweekat theUniversityofUppsalainSweden.Theauthorswarnthatallthefuelwillbe burntbeforethereisenoughcarbondioxideintheatmospheretorealize predictionsofmeltingicecapsandsearingtemperatures.Defendingtheir predictionsscientistsfromtheIntergovernmentalPanelonClimateChangesay theyconsideredarangeofestimatesofoilandgasreservesandpointoutthat coal-burningcouldeasilymakeuptheshortfall.Butallagreethatburningcoal wouldbeevenworsefortheplanet.??TheIPCC’spredictionsof globalmeltdownpushedforwardthe1997KyotoProtocolanagreementobliging signatorynationstocutCO2emissions.TheIPCCconsideredarange offuturescenariosfromunlimitedburningoffossil-fuelstoafasttransition towardsgreenerenergysources.ButgeologistsAndersSivertssonKjellAleklett andColinCampbellofUppsalaUniversitysaythereisnotenoughoilandgas lefteventhemostconservativeofthe40IPCCscenariostocometo pass.??Althoughestimatesofoilandgasreservesvarywidely theresearchersarepartofagrowinggroupofexpertswhobelievethatoil supplieswillpeakassoonas2010andgassoonafter.Theiranalysissuggests thatoilandgasreservescombinedabouttotheequivalentofabout3500 billionbarrelsofoilconsiderablylessthanthe5000billionbarrels estimatedinthemostoptimisticmodelenvisagedbytheIPCC.Eventheaverage forecastofabout8000billionbarrelsismorethantwicetheSwedishestimate oftheworld’sremainingreserves.??NebojsaNakicenovican energyeconomistattheUniversityofViennaAustriawhoheadedthe80-strong IPCCteamthatproducedtheforecastssaysthepanel’sworkstillstands.He saystheyfactoredinamuchbroaderandinternationallyacceptedrangeofoil andgasestimatesthantheconservativeSwedes.??Evenifoil andgasrunoutthere’sahugeamountofcoalundergroundthatcouldbe exploitedhesaysthatburningcoalcouldmaketheIPCCscenarioscometrue butpointsoutthatsuchaswitchwouldbedisastrous.Coalisdirtierthanoil andgasandproducesmoreCO2foreachunitofenergyaswellas releasinglargeamountsofparticulates.Hesaysthelatestanalysisisashot acrossthebowsforpolicymakers.HowmuchistheIPCC’sestimateofoilandgasreserves?
Theabilitytocontemplatetwo{{U}}contradictory{{/U}}thoughtsatonceissaidtobeamarkofgenius.
{{*HTML*}}{{B}}第二篇{{/B}} HiddenSpeciesMayBeSurprisingly Common??Cryptic隐蔽的隐藏的species--animalsthat appearidenticalbutaregeneticallyquitedistant--maybemuchmorewidespread thanpreviouslythought.Thefindingscouldhavemajorimplicationsinareas rangingfrombiodiversity生物多样性estimatesandwildlifemanagementtoour understandingofinfectiousdiseasesandevolution.??Reportsof crypticspecieshaveincreaseddramaticallyoverthepasttwodecadeswiththe adventofrelativelyinexpensiveDNA脱氧核糖核酸sequencingtechnology.Markus PfenningerandKlausSchwenkoftheGoethe-UniversitatinFrankfurtGermany analyzedallknowndataoncrypticanimalspeciesanddiscoveredthattheyare foundinequalproportionsthroughoutallmajorbranchesoftheanimalkingdom andoccurinequalnumbersinallbiogeographical生物地理学的regions.? ?Scientistshadpreviouslyspeculatedthatcrypticspecieswere predominantlyfoundininsectsandreptiles爬行动物andweremorelikelytooccur intropicalratherthantemperate温带的regions.Speciesthatareseemingly widespreadandabundantcouldinrealitybemanydifferentCrypticspeciesthat havelowpopulationsandarehighlyendangeredsaysPfenninger.Untilthe geneticinformationofallspeciesinatleastonetaxon分类单元isthoroughly studiednoonewillknowjusthowmanycrypticspeciesexistItcouldbeas highas30%Pfenningersays.??I’mextremelysurprisedbytheir resultssaysAlexSmithoftheUniversityofGuelphinOntarioCanada.It’s acalltoarmstokeepdoingthebroadkindofgeneticstudiesthatweare doing.??Samplingasmanyindividualsaspossiblescientists hopetocompleteworkonallfishandbirdsinanother5to10years.Once eitherofthesetaxonomicgroupsiscompletedPfenningersaysresearcherswill beabletodecidehowmanycrypticspeciesexistthroughouttheanimal kingdom.??ExamplesofcrypticspeciesincludetheAfrican elephant.A2001studyfoundtheelephantswereactuallytwogenetically distinctnon-interbreeding非杂交繁殖的speciestheAfricanbushelephantandthe Africanelephant.Thespeciesarecurrentlylistedasvulnerableandthreatened respectivelybytheWorldConservationUnionWCU.??The reclassificationsaremorethananacademicexercise.Theydefinepopulations thathaveevolvedindependentlyofeachotherandwhosegeneticdifferencescan havesignificantconsequences.??Intheearly1900s misidentificationofmosquitospeciesbasedonmorphologyconfused:attemptsto controlmalaria疟疾inEurope.Ultimatelywhatwasthoughttobeasingle specieswasactuallymadeupofsixsibling同胞同属speciesonlythreeofwhich transmittedthedisease.Thebasicunitinbiologyisalwaysthespeciesand youhavetoknowwhatyouaredealingwithPfenningersays.Muchprevious researchisnownolongerusedhesaysbecauseitisnotclearwhatspecies wasbeingstudied.WhichofthefollowingaboutthesignificanceoftheresearchoncrypticspeciesisNOTtrue?
Crayfishsmallfreshwatercrustaceansimilartolobstersare{{U}}consumed{{/U}}byinhabitantsoftheMississippiRiverBasin.
{{*HTML*}}下面的短文有15处空白请根据短文内容为每处空白确定1个最佳选项 CellPhoneLetsYourSecret Out??Yourcellphoneholdssecretsaboutyou. Besidesthenamesand{{U}}?51?{{/U}}thatyou’veprogrammedintoit tracesofyourDNAlinger逗留onthedeviceaccordingtoanewstudy.? ?DNAisgenetic遗传的materialthat{{U}}?52?{{/U}}ineverycell. LikeyourfingerprintyourDNAisuniquetoyou{{U}}?53?{{/U}}you haveanidenticaltwin.ScientiststodayroutinelyanalyzeDNAinblood saliva涎唾液orhairleft{{U}}?54?{{/U}}atthesceneofacrime.The resultsoftenhelpdetectivesidentify{{U}}?55?{{/U}}andtheir victims.Yourcellphonecanrevealmoreaboutyou{{U}}?56?{{/U}}you mightthink.??MeghanJ.McFaddenascientistatMcMaster UniversityinHamiltonOntarioheardaboutacrimeinwhichthesuspectbled ontoacellphoneandlaterdroppedthe{{U}}?57?{{/U}}Thismadeher wonderwhethertracesofDNAlingeredoncellphones--evenwhennobloodwas involved.{{U}}?58?{{/U}}sheandcolleagueMargaretWallaceofthe CityUniversityofNewYorkanalyzedtheflip-openphones翻盖手机of10 volunteers.Theyusedswabs药签tocollect{{U}}?59?{{/U}}tracesof theusersfromtwopartsofthephone:theoutsidewheretheuserholdsitand the{{U}}?60?{{/U}}whichisplacedattheuser’sear.? ?Thescientistsscrubbed用力擦洗擦净thephonesusingasolutionmademostly {{U}}?61?{{/U}}alcohol.Theaimofwashingwastoremoveall detectabletracesofDNA.Theownersgottheirphones??{{U}} ?62?{{/U}}foranotherweek.Thentheresearcherscollectedthe phonesandrepeatedtheswabbingofeachphoneoncemore.??The scientistsdiscoveredDNAthat{{U}}?63?{{/U}}tothephone’sspeaker oneachofthephones.Bettersampleswerecollectedfromtheoutsideofeach phonebutthoseswabsalsopickedupDNAthatbelongedtootherpeoplewhohad apparentlyalsohandledthephone.{{U}}?64?{{/U}}DNAshowedupeven inswabsthatweretakenimmediatelyafterthephoneswerescrubbed.That suggeststhatwashingwon’tremovealltracesofevidencefromacriminal’s device.Socellphonescannowbeaddedtothe{{U}}?65?{{/U}}ofclues thatcanclinch确定决定acrime-scene investigation.
{{*HTML*}}下面的短文有15处空白请根据短文内容为每处空白确定1个最佳选项 CellPhoneLetsYourSecret Out??Yourcellphoneholdssecretsaboutyou. Besidesthenamesand{{U}}?51?{{/U}}thatyou’veprogrammedintoit tracesofyourDNAlinger逗留onthedeviceaccordingtoanewstudy.? ?DNAisgenetic遗传的materialthat{{U}}?52?{{/U}}ineverycell. LikeyourfingerprintyourDNAisuniquetoyou{{U}}?53?{{/U}}you haveanidenticaltwin.ScientiststodayroutinelyanalyzeDNAinblood saliva涎唾液orhairleft{{U}}?54?{{/U}}atthesceneofacrime.The resultsoftenhelpdetectivesidentify{{U}}?55?{{/U}}andtheir victims.Yourcellphonecanrevealmoreaboutyou{{U}}?56?{{/U}}you mightthink.??MeghanJ.McFaddenascientistatMcMaster UniversityinHamiltonOntarioheardaboutacrimeinwhichthesuspectbled ontoacellphoneandlaterdroppedthe{{U}}?57?{{/U}}Thismadeher wonderwhethertracesofDNAlingeredoncellphones--evenwhennobloodwas involved.{{U}}?58?{{/U}}sheandcolleagueMargaretWallaceofthe CityUniversityofNewYorkanalyzedtheflip-openphones翻盖手机of10 volunteers.Theyusedswabs药签tocollect{{U}}?59?{{/U}}tracesof theusersfromtwopartsofthephone:theoutsidewheretheuserholdsitand the{{U}}?60?{{/U}}whichisplacedattheuser’sear.? ?Thescientistsscrubbed用力擦洗擦净thephonesusingasolutionmademostly {{U}}?61?{{/U}}alcohol.Theaimofwashingwastoremoveall detectabletracesofDNA.Theownersgottheirphones??{{U}} ?62?{{/U}}foranotherweek.Thentheresearcherscollectedthe phonesandrepeatedtheswabbingofeachphoneoncemore.??The scientistsdiscoveredDNAthat{{U}}?63?{{/U}}tothephone’sspeaker oneachofthephones.Bettersampleswerecollectedfromtheoutsideofeach phonebutthoseswabsalsopickedupDNAthatbelongedtootherpeoplewhohad apparentlyalsohandledthephone.{{U}}?64?{{/U}}DNAshowedupeven inswabsthatweretakenimmediatelyafterthephoneswerescrubbed.That suggeststhatwashingwon’tremovealltracesofevidencefromacriminal’s device.Socellphonescannowbeaddedtothe{{U}}?65?{{/U}}ofclues thatcanclinch确定决定acrime-scene investigation.
MaryMcCarthy’ssatiresare{{U}}couched{{/U}}inaprosestylethathasaclassicprecision.
{{*HTML*}}下面的短文有15处空白请根据短文内容为每处空白确定1个最佳选项 CellPhoneLetsYourSecret Out??Yourcellphoneholdssecretsaboutyou. Besidesthenamesand{{U}}?51?{{/U}}thatyou’veprogrammedintoit tracesofyourDNAlinger逗留onthedeviceaccordingtoanewstudy.? ?DNAisgenetic遗传的materialthat{{U}}?52?{{/U}}ineverycell. LikeyourfingerprintyourDNAisuniquetoyou{{U}}?53?{{/U}}you haveanidenticaltwin.ScientiststodayroutinelyanalyzeDNAinblood saliva涎唾液orhairleft{{U}}?54?{{/U}}atthesceneofacrime.The resultsoftenhelpdetectivesidentify{{U}}?55?{{/U}}andtheir victims.Yourcellphonecanrevealmoreaboutyou{{U}}?56?{{/U}}you mightthink.??MeghanJ.McFaddenascientistatMcMaster UniversityinHamiltonOntarioheardaboutacrimeinwhichthesuspectbled ontoacellphoneandlaterdroppedthe{{U}}?57?{{/U}}Thismadeher wonderwhethertracesofDNAlingeredoncellphones--evenwhennobloodwas involved.{{U}}?58?{{/U}}sheandcolleagueMargaretWallaceofthe CityUniversityofNewYorkanalyzedtheflip-openphones翻盖手机of10 volunteers.Theyusedswabs药签tocollect{{U}}?59?{{/U}}tracesof theusersfromtwopartsofthephone:theoutsidewheretheuserholdsitand the{{U}}?60?{{/U}}whichisplacedattheuser’sear.? ?Thescientistsscrubbed用力擦洗擦净thephonesusingasolutionmademostly {{U}}?61?{{/U}}alcohol.Theaimofwashingwastoremoveall detectabletracesofDNA.Theownersgottheirphones??{{U}} ?62?{{/U}}foranotherweek.Thentheresearcherscollectedthe phonesandrepeatedtheswabbingofeachphoneoncemore.??The scientistsdiscoveredDNAthat{{U}}?63?{{/U}}tothephone’sspeaker oneachofthephones.Bettersampleswerecollectedfromtheoutsideofeach phonebutthoseswabsalsopickedupDNAthatbelongedtootherpeoplewhohad apparentlyalsohandledthephone.{{U}}?64?{{/U}}DNAshowedupeven inswabsthatweretakenimmediatelyafterthephoneswerescrubbed.That suggeststhatwashingwon’tremovealltracesofevidencefromacriminal’s device.Socellphonescannowbeaddedtothe{{U}}?65?{{/U}}ofclues thatcanclinch确定决定acrime-scene investigation.
{{*HTML*}}? ?阅读下面这篇短文短文后有2项测试任务1第23～26题要求从所给的6个选项中为第2～5段每段选择1个正确的小标题2第27～30题要求从所给的6个选项中选择4个正确选项分别完成每个句子 ?????????? ??????????? ????{{B}}Earthquake{{/B}}??1.Everyyear earthquakesareresponsibleforalargenumberofdeathsandavastamountof destructioninvariouspartsoftheworld.Mostofthesedamagingearthquakes occureitherinanarrowbeltwhichsurroundsthePacificOceanorinaline whichextendsfromBurmatotheAlpsinEurope.Someofthedestructionis directlycausedbythequakeitself.Anexampleofthisisthecollapseof buildingsasaresultofthequakeitself.Otherdamageresultsfromland-slides ormajorfireswhichareinitiatedbythequake.??2.Thereare aboutamillionquakesayear.Fortunatelyhowevernotallofthemare destructive.TheintensityofanearthquakeismeasuredontheRichterScale whichgoesfrom0upward.Thehighestscalerecordedtodateis8.9.Major damagegenerallyoccursfromquakesrangingupwardsfrom6.0.??3. Theactualcauseofthequakeitselfisthebreakingofrocksatorbelowthe earth’ssurface.Thisisproducedbypressurewhichscientistsbelievemaybe duetoanumberofreasonstwoofwhicharetheexpansionandcontractionof theearth’scrustandcontinentaldrift.??4.Inordertolimit thedamageandtopreventsomeofthesufferingresultingfromearthquakes scientistsareworkinganwaystoenableaccurateprediction.Special instrumentsareusedtohelppeoplerecordforexampleshakingoftheearth. Scientistsaretryingtofindmethodsthatwillenablethemtoindicatethe exacttimelocationandsizeofanearthquake.??5.Certain phenomenahavebeenobservedwhicharebelievedtobethesignsofimminent earthquakes.Theseincludestrangebehavioursofsomeanimalsthechangesin thecontentofmineralwateretc.Themagneticpropertiesofrocksmayalso displayspecialpatternbeforemajorearthquakeshappen.Notalldamageduringanearthquakeiscaused______.
{{*HTML*}}下面的短文有15处空白请根据短文内容为每处空白确定1个最佳选项 CellPhoneLetsYourSecret Out??Yourcellphoneholdssecretsaboutyou. Besidesthenamesand{{U}}?51?{{/U}}thatyou’veprogrammedintoit tracesofyourDNAlinger逗留onthedeviceaccordingtoanewstudy.? ?DNAisgenetic遗传的materialthat{{U}}?52?{{/U}}ineverycell. LikeyourfingerprintyourDNAisuniquetoyou{{U}}?53?{{/U}}you haveanidenticaltwin.ScientiststodayroutinelyanalyzeDNAinblood saliva涎唾液orhairleft{{U}}?54?{{/U}}atthesceneofacrime.The resultsoftenhelpdetectivesidentify{{U}}?55?{{/U}}andtheir victims.Yourcellphonecanrevealmoreaboutyou{{U}}?56?{{/U}}you mightthink.??MeghanJ.McFaddenascientistatMcMaster UniversityinHamiltonOntarioheardaboutacrimeinwhichthesuspectbled ontoacellphoneandlaterdroppedthe{{U}}?57?{{/U}}Thismadeher wonderwhethertracesofDNAlingeredoncellphones--evenwhennobloodwas involved.{{U}}?58?{{/U}}sheandcolleagueMargaretWallaceofthe CityUniversityofNewYorkanalyzedtheflip-openphones翻盖手机of10 volunteers.Theyusedswabs药签tocollect{{U}}?59?{{/U}}tracesof theusersfromtwopartsofthephone:theoutsidewheretheuserholdsitand the{{U}}?60?{{/U}}whichisplacedattheuser’sear.? ?Thescientistsscrubbed用力擦洗擦净thephonesusingasolutionmademostly {{U}}?61?{{/U}}alcohol.Theaimofwashingwastoremoveall detectabletracesofDNA.Theownersgottheirphones??{{U}} ?62?{{/U}}foranotherweek.Thentheresearcherscollectedthe phonesandrepeatedtheswabbingofeachphoneoncemore.??The scientistsdiscoveredDNAthat{{U}}?63?{{/U}}tothephone’sspeaker oneachofthephones.Bettersampleswerecollectedfromtheoutsideofeach phonebutthoseswabsalsopickedupDNAthatbelongedtootherpeoplewhohad apparentlyalsohandledthephone.{{U}}?64?{{/U}}DNAshowedupeven inswabsthatweretakenimmediatelyafterthephoneswerescrubbed.That suggeststhatwashingwon’tremovealltracesofevidencefromacriminal’s device.Socellphonescannowbeaddedtothe{{U}}?65?{{/U}}ofclues thatcanclinch确定决定acrime-scene investigation.
{{*HTML*}}??阅读下面这篇短文短文后列出7个句子请根据短文的内容对每个句子做出判断 ??????? ??????????? {{B}}HelpYourChildBecomeaReader{{/B}}??Encouragingearlyreading skillscanbuildapathtoalifelong终身的loveofreadingandcanhelpyour childgetaheadstartinschool.Whilereadingtoyourchildisstillthemost importantthingyoucandotobuildreadingskillstherearemanytechniques thatcanhelp.??Makereadingfun.Playgameswithyourchildas youread.Manytraditionalchildren’sgamescanbeadaptedtoencouragereading skills.??WhilereadingorduringplaytellyourchildIspy withmylittleeyesomethingthatbeginswiththeletterb.Helpthechild findsomethingonthepageorintheroomthatbeginswiththatletter.For example.Iseeabarn.Thiscanalsobeusedtoteachbeginninglettersounds. Ispywithmylittleeyesomethingthatbeginswiththesound‘s’.Helpthe childfindawordthatbeginswiththessound.??Inthis variationonthepopulargameinstructthechildthatSimonsays‘pointto somethingthatstartswiththelettern.’Thechildcanthenfindanobjectin theroomorabodypartsuchasthenosethatstartswiththeletter presented.Thiscanalsobeusedtoteachbeginningsounds.??Make agameoutofrhyming押韵wordsbymakingupsillywordstorhymewiththe child’snameoffavoritetoys.Thissetsthestageforrhymingrealwordsby showingthechildthesimilaritiesofsounds.Asthechildmastersmakingupthe wordsbeginrhymingrealwordstooneanother.??Tipstoraisea successfulreader:??Putbooksinplaceswherethechildplays.If booksareeasilyaccessiblechildrenaremorelikelytopickthemup.? ?Letchildrenreadtoyoubylookingatpictures.Makingupstoriestogo alongwithillustrationshelpschildrendiscoverhowwordsrelateto pictures.??Takebooksalongontripsorevenshortvisitstothe doctor’sofficeorgrocerystore.??Havechildrenhelpyoushop. Readinggrocerylistsandlookingforspecificitemshelpsbuildsight vocabulary.Whenplayingagameyoushouldaskyourchildtofindsomethingstartingwiththeletterbinsteadofc.
{{*HTML*}}{{B}}第二篇{{/B}} HiddenSpeciesMayBeSurprisingly Common??Cryptic隐蔽的隐藏的species--animalsthat appearidenticalbutaregeneticallyquitedistant--maybemuchmorewidespread thanpreviouslythought.Thefindingscouldhavemajorimplicationsinareas rangingfrombiodiversity生物多样性estimatesandwildlifemanagementtoour understandingofinfectiousdiseasesandevolution.??Reportsof crypticspecieshaveincreaseddramaticallyoverthepasttwodecadeswiththe adventofrelativelyinexpensiveDNA脱氧核糖核酸sequencingtechnology.Markus PfenningerandKlausSchwenkoftheGoethe-UniversitatinFrankfurtGermany analyzedallknowndataoncrypticanimalspeciesanddiscoveredthattheyare foundinequalproportionsthroughoutallmajorbranchesoftheanimalkingdom andoccurinequalnumbersinallbiogeographical生物地理学的regions.? ?Scientistshadpreviouslyspeculatedthatcrypticspecieswere predominantlyfoundininsectsandreptiles爬行动物andweremorelikelytooccur intropicalratherthantemperate温带的regions.Speciesthatareseemingly widespreadandabundantcouldinrealitybemanydifferentCrypticspeciesthat havelowpopulationsandarehighlyendangeredsaysPfenninger.Untilthe geneticinformationofallspeciesinatleastonetaxon分类单元isthoroughly studiednoonewillknowjusthowmanycrypticspeciesexistItcouldbeas highas30%Pfenningersays.??I’mextremelysurprisedbytheir resultssaysAlexSmithoftheUniversityofGuelphinOntarioCanada.It’s acalltoarmstokeepdoingthebroadkindofgeneticstudiesthatweare doing.??Samplingasmanyindividualsaspossiblescientists hopetocompleteworkonallfishandbirdsinanother5to10years.Once eitherofthesetaxonomicgroupsiscompletedPfenningersaysresearcherswill beabletodecidehowmanycrypticspeciesexistthroughouttheanimal kingdom.??ExamplesofcrypticspeciesincludetheAfrican elephant.A2001studyfoundtheelephantswereactuallytwogenetically distinctnon-interbreeding非杂交繁殖的speciestheAfricanbushelephantandthe Africanelephant.Thespeciesarecurrentlylistedasvulnerableandthreatened respectivelybytheWorldConservationUnionWCU.??The reclassificationsaremorethananacademicexercise.Theydefinepopulations thathaveevolvedindependentlyofeachotherandwhosegeneticdifferencescan havesignificantconsequences.??Intheearly1900s misidentificationofmosquitospeciesbasedonmorphologyconfused:attemptsto controlmalaria疟疾inEurope.Ultimatelywhatwasthoughttobeasingle specieswasactuallymadeupofsixsibling同胞同属speciesonlythreeofwhich transmittedthedisease.Thebasicunitinbiologyisalwaysthespeciesand youhavetoknowwhatyouaredealingwithPfenningersays.Muchprevious researchisnownolongerusedhesaysbecauseitisnotclearwhatspecies wasbeingstudied.PeoplewereconfusedintheirattemptstocontrolmalariainEuropeintheearly1900sbecausescientists
{{*HTML*}}? ?阅读下面这篇短文短文后有2项测试任务1第23～26题要求从所给的6个选项中为第2～5段每段选择1个正确的小标题2第27～30题要求从所给的6个选项中选择4个正确选项分别完成每个句子 ?????????? ??????????? ????{{B}}Earthquake{{/B}}??1.Everyyear earthquakesareresponsibleforalargenumberofdeathsandavastamountof destructioninvariouspartsoftheworld.Mostofthesedamagingearthquakes occureitherinanarrowbeltwhichsurroundsthePacificOceanorinaline whichextendsfromBurmatotheAlpsinEurope.Someofthedestructionis directlycausedbythequakeitself.Anexampleofthisisthecollapseof buildingsasaresultofthequakeitself.Otherdamageresultsfromland-slides ormajorfireswhichareinitiatedbythequake.??2.Thereare aboutamillionquakesayear.Fortunatelyhowevernotallofthemare destructive.TheintensityofanearthquakeismeasuredontheRichterScale whichgoesfrom0upward.Thehighestscalerecordedtodateis8.9.Major damagegenerallyoccursfromquakesrangingupwardsfrom6.0.??3. Theactualcauseofthequakeitselfisthebreakingofrocksatorbelowthe earth’ssurface.Thisisproducedbypressurewhichscientistsbelievemaybe duetoanumberofreasonstwoofwhicharetheexpansionandcontractionof theearth’scrustandcontinentaldrift.??4.Inordertolimit thedamageandtopreventsomeofthesufferingresultingfromearthquakes scientistsareworkinganwaystoenableaccurateprediction.Special instrumentsareusedtohelppeoplerecordforexampleshakingoftheearth. Scientistsaretryingtofindmethodsthatwillenablethemtoindicatethe exacttimelocationandsizeofanearthquake.??5.Certain phenomenahavebeenobservedwhicharebelievedtobethesignsofimminent earthquakes.Theseincludestrangebehavioursofsomeanimalsthechangesin thecontentofmineralwateretc.Themagneticpropertiesofrocksmayalso displayspecialpatternbeforemajorearthquakeshappen.Paragraph2______A.Earthquake’sForecast
Coldaircausesthearteriesaroundtheheartto{{U}}constrict{{/U}}.
{{*HTML*}}下面的短文有5处空白短文后有6个句子其中5个取自短文请根据短文内容将其分别放回原有位置以恢复文章原貌 WhydoPeopleShrink?? ?DidyoueverseethemovieHoneyIshrunkthekids?It’sabouta wacky乖僻的dadwho’salsoascientistwhoaccidentally偶然的shrinkshiskids withhishomemademiniaturizing使小型化invention.Oops!Thekidsspendtherest ofthemovieastinypeoplewhoarebarelyvisiblewhiletryingtogetbackto theirnormalsize.??{{U}}?46?{{/U}}Ittakesplaceover yearsandmayadduptoonlyoneinchorsooffoftheiradultheightmaybea littlemoremaybelessandthiskindofshrinkingcan’tbemagically reversedalthoughtherearethingsthatcanbedonetostopitorslowitdown. Butwhydoesshrinkinghappenatall???{{U}}?47?{{/U}}. Aspeoplegetoldertheygenerallylosesomemuscleandfatfromtheirbodies aspartofthenaturalagingprocess.Gravitytheforcethatkeepsyourfeeton thegroundtakeholdandthebonesinthespinecalledvertebrae椎骨may breakdownordegenerateandstarttocollapseintooneanother.{{U}}?48 ?{{/U}}.Butperhapsthemostcommonreasonwhysomeolderpeopleshrinkis becauseofosteoporosis.??Osteoporosis骨质疏松症occurswhentoo muchspongy海绵bonetissuewhichisfoundinsideofmostbonesisbrokendown andnotenoughnewbonematerialismade.{{U}}?49?{{/U}}.Bonesbecome smallerandweakerandcaneasilybreakifsomeonewithosteoporosisisinjured. Olderpeople--especiallywomenwhogenerallyhavesmallerandlighterbones tobeginwith--aremorelikelytodeveloposteoporosis.Asyearsgobya personwithosteoporosisshrinksalittlebit.??Didyouknowthat everydayyoudoashrinkingact?Youaren’tastallattheendofthedayas youareatthebeginning.{{U}}?50?{{/U}}.Don’tworrythough.Once yougetagoodnight’srestyourbodyrecoversandthenextmorningyou’re standingtallagain.??A.Theyenduppressingclosertogether whichmakesapersonlosealittleheightandbecomeshorter.??B. That’sbecauseasthedaygoesonwaterinthedisksofthespinegets compressedsqueezedduetogravitymakingyoujustatinybit shorter.??C.Overtimeboneissaidtobelostbecauseit’snot beingreplaced.??D.Luckilytherearethingsthatpeoplecando topreventshrinking.??E.Forolderpeopleshrinkingisn’tthat dramaticorsuddenatall.??F.Thereareafewreasons.
{{*HTML*}}? ?阅读下面这篇短文短文后有2项测试任务1第23～26题要求从所给的6个选项中为第2～5段每段选择1个正确的小标题2第27～30题要求从所给的6个选项中选择4个正确选项分别完成每个句子 ?????????? ??????????? ????{{B}}Earthquake{{/B}}??1.Everyyear earthquakesareresponsibleforalargenumberofdeathsandavastamountof destructioninvariouspartsoftheworld.Mostofthesedamagingearthquakes occureitherinanarrowbeltwhichsurroundsthePacificOceanorinaline whichextendsfromBurmatotheAlpsinEurope.Someofthedestructionis directlycausedbythequakeitself.Anexampleofthisisthecollapseof buildingsasaresultofthequakeitself.Otherdamageresultsfromland-slides ormajorfireswhichareinitiatedbythequake.??2.Thereare aboutamillionquakesayear.Fortunatelyhowevernotallofthemare destructive.TheintensityofanearthquakeismeasuredontheRichterScale whichgoesfrom0upward.Thehighestscalerecordedtodateis8.9.Major damagegenerallyoccursfromquakesrangingupwardsfrom6.0.??3. Theactualcauseofthequakeitselfisthebreakingofrocksatorbelowthe earth’ssurface.Thisisproducedbypressurewhichscientistsbelievemaybe duetoanumberofreasonstwoofwhicharetheexpansionandcontractionof theearth’scrustandcontinentaldrift.??4.Inordertolimit thedamageandtopreventsomeofthesufferingresultingfromearthquakes scientistsareworkinganwaystoenableaccurateprediction.Special instrumentsareusedtohelppeoplerecordforexampleshakingoftheearth. Scientistsaretryingtofindmethodsthatwillenablethemtoindicatethe exacttimelocationandsizeofanearthquake.??5.Certain phenomenahavebeenobservedwhicharebelievedtobethesignsofimminent earthquakes.Theseincludestrangebehavioursofsomeanimalsthechangesin thecontentofmineralwateretc.Themagneticpropertiesofrocksmayalso displayspecialpatternbeforemajorearthquakeshappen.Paragraph4______
{{*HTML*}}??阅读下面这篇短文短文后列出7个句子请根据短文的内容对每个句子做出判断 ??????? ??????????? {{B}}HelpYourChildBecomeaReader{{/B}}??Encouragingearlyreading skillscanbuildapathtoalifelong终身的loveofreadingandcanhelpyour childgetaheadstartinschool.Whilereadingtoyourchildisstillthemost importantthingyoucandotobuildreadingskillstherearemanytechniques thatcanhelp.??Makereadingfun.Playgameswithyourchildas youread.Manytraditionalchildren’sgamescanbeadaptedtoencouragereading skills.??WhilereadingorduringplaytellyourchildIspy withmylittleeyesomethingthatbeginswiththeletterb.Helpthechild findsomethingonthepageorintheroomthatbeginswiththatletter.For example.Iseeabarn.Thiscanalsobeusedtoteachbeginninglettersounds. Ispywithmylittleeyesomethingthatbeginswiththesound‘s’.Helpthe childfindawordthatbeginswiththessound.??Inthis variationonthepopulargameinstructthechildthatSimonsays‘pointto somethingthatstartswiththelettern.’Thechildcanthenfindanobjectin theroomorabodypartsuchasthenosethatstartswiththeletter presented.Thiscanalsobeusedtoteachbeginningsounds.??Make agameoutofrhyming押韵wordsbymakingupsillywordstorhymewiththe child’snameoffavoritetoys.Thissetsthestageforrhymingrealwordsby showingthechildthesimilaritiesofsounds.Asthechildmastersmakingupthe wordsbeginrhymingrealwordstooneanother.??Tipstoraisea successfulreader:??Putbooksinplaceswherethechildplays.If booksareeasilyaccessiblechildrenaremorelikelytopickthemup.? ?Letchildrenreadtoyoubylookingatpictures.Makingupstoriestogo alongwithillustrationshelpschildrendiscoverhowwordsrelateto pictures.??Takebooksalongontripsorevenshortvisitstothe doctor’sofficeorgrocerystore.??Havechildrenhelpyoushop. Readinggrocerylistsandlookingforspecificitemshelpsbuildsight vocabulary.Computergamescanbeusedtohelpchildrendeveloptheirreadingskills.
{{*HTML*}}下面的短文有15处空白请根据短文内容为每处空白确定1个最佳选项 CellPhoneLetsYourSecret Out??Yourcellphoneholdssecretsaboutyou. Besidesthenamesand{{U}}?51?{{/U}}thatyou’veprogrammedintoit tracesofyourDNAlinger逗留onthedeviceaccordingtoanewstudy.? ?DNAisgenetic遗传的materialthat{{U}}?52?{{/U}}ineverycell. LikeyourfingerprintyourDNAisuniquetoyou{{U}}?53?{{/U}}you haveanidenticaltwin.ScientiststodayroutinelyanalyzeDNAinblood saliva涎唾液orhairleft{{U}}?54?{{/U}}atthesceneofacrime.The resultsoftenhelpdetectivesidentify{{U}}?55?{{/U}}andtheir victims.Yourcellphonecanrevealmoreaboutyou{{U}}?56?{{/U}}you mightthink.??MeghanJ.McFaddenascientistatMcMaster UniversityinHamiltonOntarioheardaboutacrimeinwhichthesuspectbled ontoacellphoneandlaterdroppedthe{{U}}?57?{{/U}}Thismadeher wonderwhethertracesofDNAlingeredoncellphones--evenwhennobloodwas involved.{{U}}?58?{{/U}}sheandcolleagueMargaretWallaceofthe CityUniversityofNewYorkanalyzedtheflip-openphones翻盖手机of10 volunteers.Theyusedswabs药签tocollect{{U}}?59?{{/U}}tracesof theusersfromtwopartsofthephone:theoutsidewheretheuserholdsitand the{{U}}?60?{{/U}}whichisplacedattheuser’sear.? ?Thescientistsscrubbed用力擦洗擦净thephonesusingasolutionmademostly {{U}}?61?{{/U}}alcohol.Theaimofwashingwastoremoveall detectabletracesofDNA.Theownersgottheirphones??{{U}} ?62?{{/U}}foranotherweek.Thentheresearcherscollectedthe phonesandrepeatedtheswabbingofeachphoneoncemore.??The scientistsdiscoveredDNAthat{{U}}?63?{{/U}}tothephone’sspeaker oneachofthephones.Bettersampleswerecollectedfromtheoutsideofeach phonebutthoseswabsalsopickedupDNAthatbelongedtootherpeoplewhohad apparentlyalsohandledthephone.{{U}}?64?{{/U}}DNAshowedupeven inswabsthatweretakenimmediatelyafterthephoneswerescrubbed.That suggeststhatwashingwon’tremovealltracesofevidencefromacriminal’s device.Socellphonescannowbeaddedtothe{{U}}?65?{{/U}}ofclues thatcanclinch确定决定acrime-scene investigation.
{{*HTML*}}下面的短文有5处空白短文后有6个句子其中5个取自短文请根据短文内容将其分别放回原有位置以恢复文章原貌 WhydoPeopleShrink?? ?DidyoueverseethemovieHoneyIshrunkthekids?It’sabouta wacky乖僻的dadwho’salsoascientistwhoaccidentally偶然的shrinkshiskids withhishomemademiniaturizing使小型化invention.Oops!Thekidsspendtherest ofthemovieastinypeoplewhoarebarelyvisiblewhiletryingtogetbackto theirnormalsize.??{{U}}?46?{{/U}}Ittakesplaceover yearsandmayadduptoonlyoneinchorsooffoftheiradultheightmaybea littlemoremaybelessandthiskindofshrinkingcan’tbemagically reversedalthoughtherearethingsthatcanbedonetostopitorslowitdown. Butwhydoesshrinkinghappenatall???{{U}}?47?{{/U}}. Aspeoplegetoldertheygenerallylosesomemuscleandfatfromtheirbodies aspartofthenaturalagingprocess.Gravitytheforcethatkeepsyourfeeton thegroundtakeholdandthebonesinthespinecalledvertebrae椎骨may breakdownordegenerateandstarttocollapseintooneanother.{{U}}?48 ?{{/U}}.Butperhapsthemostcommonreasonwhysomeolderpeopleshrinkis becauseofosteoporosis.??Osteoporosis骨质疏松症occurswhentoo muchspongy海绵bonetissuewhichisfoundinsideofmostbonesisbrokendown andnotenoughnewbonematerialismade.{{U}}?49?{{/U}}.Bonesbecome smallerandweakerandcaneasilybreakifsomeonewithosteoporosisisinjured. Olderpeople--especiallywomenwhogenerallyhavesmallerandlighterbones tobeginwith--aremorelikelytodeveloposteoporosis.Asyearsgobya personwithosteoporosisshrinksalittlebit.??Didyouknowthat everydayyoudoashrinkingact?Youaren’tastallattheendofthedayas youareatthebeginning.{{U}}?50?{{/U}}.Don’tworrythough.Once yougetagoodnight’srestyourbodyrecoversandthenextmorningyou’re standingtallagain.??A.Theyenduppressingclosertogether whichmakesapersonlosealittleheightandbecomeshorter.??B. That’sbecauseasthedaygoesonwaterinthedisksofthespinegets compressedsqueezedduetogravitymakingyoujustatinybit shorter.??C.Overtimeboneissaidtobelostbecauseit’snot beingreplaced.??D.Luckilytherearethingsthatpeoplecando topreventshrinking.??E.Forolderpeopleshrinkingisn’tthat dramaticorsuddenatall.??F.Thereareafewreasons.{{*HTML*}}
Whathesaidwas{{U}}contrariwise{{/U}}towhatweexpected.
Needlepointhasalwaysbeenanelegantand{{U}}costly{{/U}}formofembroidery.
{{*HTML*}}{{B}}第三篇{{/B}} TooLittleforGlobalWarming? ?Oilandgaswillrunouttoofastfordoomsdayglobalwarmingscenariosto materializeaccordingtoacontroversialnewanalysispresentedthisweekat theUniversityofUppsalainSweden.Theauthorswarnthatallthefuelwillbe burntbeforethereisenoughcarbondioxideintheatmospheretorealize predictionsofmeltingicecapsandsearingtemperatures.Defendingtheir predictionsscientistsfromtheIntergovernmentalPanelonClimateChangesay theyconsideredarangeofestimatesofoilandgasreservesandpointoutthat coal-burningcouldeasilymakeuptheshortfall.Butallagreethatburningcoal wouldbeevenworsefortheplanet.??TheIPCC’spredictionsof globalmeltdownpushedforwardthe1997KyotoProtocolanagreementobliging signatorynationstocutCO2emissions.TheIPCCconsideredarange offuturescenariosfromunlimitedburningoffossil-fuelstoafasttransition towardsgreenerenergysources.ButgeologistsAndersSivertssonKjellAleklett andColinCampbellofUppsalaUniversitysaythereisnotenoughoilandgas lefteventhemostconservativeofthe40IPCCscenariostocometo pass.??Althoughestimatesofoilandgasreservesvarywidely theresearchersarepartofagrowinggroupofexpertswhobelievethatoil supplieswillpeakassoonas2010andgassoonafter.Theiranalysissuggests thatoilandgasreservescombinedabouttotheequivalentofabout3500 billionbarrelsofoilconsiderablylessthanthe5000billionbarrels estimatedinthemostoptimisticmodelenvisagedbytheIPCC.Eventheaverage forecastofabout8000billionbarrelsismorethantwicetheSwedishestimate oftheworld’sremainingreserves.??NebojsaNakicenovican energyeconomistattheUniversityofViennaAustriawhoheadedthe80-strong IPCCteamthatproducedtheforecastssaysthepanel’sworkstillstands.He saystheyfactoredinamuchbroaderandinternationallyacceptedrangeofoil andgasestimatesthantheconservativeSwedes.??Evenifoil andgasrunoutthere’sahugeamountofcoalundergroundthatcouldbe exploitedhesaysthatburningcoalcouldmaketheIPCCscenarioscometrue butpointsoutthatsuchaswitchwouldbedisastrous.Coalisdirtierthanoil andgasandproducesmoreCO2foreachunitofenergyaswellas releasinglargeamountsofparticulates.Hesaysthelatestanalysisisashot acrossthebowsforpolicymakers.AccordingtoIPCCwhatcanmakeuptheshortfalloftheoilandgasreserves?
Thecheetahis{{U}}considered{{/U}}thefastestofalllandanimals.
{{*HTML*}}下面的短文有5处空白短文后有6个句子其中5个取自短文请根据短文内容将其分别放回原有位置以恢复文章原貌 WhydoPeopleShrink?? ?DidyoueverseethemovieHoneyIshrunkthekids?It’sabouta wacky乖僻的dadwho’salsoascientistwhoaccidentally偶然的shrinkshiskids withhishomemademiniaturizing使小型化invention.Oops!Thekidsspendtherest ofthemovieastinypeoplewhoarebarelyvisiblewhiletryingtogetbackto theirnormalsize.??{{U}}?46?{{/U}}Ittakesplaceover yearsandmayadduptoonlyoneinchorsooffoftheiradultheightmaybea littlemoremaybelessandthiskindofshrinkingcan’tbemagically reversedalthoughtherearethingsthatcanbedonetostopitorslowitdown. Butwhydoesshrinkinghappenatall???{{U}}?47?{{/U}}. Aspeoplegetoldertheygenerallylosesomemuscleandfatfromtheirbodies aspartofthenaturalagingprocess.Gravitytheforcethatkeepsyourfeeton thegroundtakeholdandthebonesinthespinecalledvertebrae椎骨may breakdownordegenerateandstarttocollapseintooneanother.{{U}}?48 ?{{/U}}.Butperhapsthemostcommonreasonwhysomeolderpeopleshrinkis becauseofosteoporosis.??Osteoporosis骨质疏松症occurswhentoo muchspongy海绵bonetissuewhichisfoundinsideofmostbonesisbrokendown andnotenoughnewbonematerialismade.{{U}}?49?{{/U}}.Bonesbecome smallerandweakerandcaneasilybreakifsomeonewithosteoporosisisinjured. Olderpeople--especiallywomenwhogenerallyhavesmallerandlighterbones tobeginwith--aremorelikelytodeveloposteoporosis.Asyearsgobya personwithosteoporosisshrinksalittlebit.??Didyouknowthat everydayyoudoashrinkingact?Youaren’tastallattheendofthedayas youareatthebeginning.{{U}}?50?{{/U}}.Don’tworrythough.Once yougetagoodnight’srestyourbodyrecoversandthenextmorningyou’re standingtallagain.??A.Theyenduppressingclosertogether whichmakesapersonlosealittleheightandbecomeshorter.??B. That’sbecauseasthedaygoesonwaterinthedisksofthespinegets compressedsqueezedduetogravitymakingyoujustatinybit shorter.??C.Overtimeboneissaidtobelostbecauseit’snot beingreplaced.??D.Luckilytherearethingsthatpeoplecando topreventshrinking.??E.Forolderpeopleshrinkingisn’tthat dramaticorsuddenatall.??F.Thereareafewreasons.
{{*HTML*}}? ?阅读下面这篇短文短文后有2项测试任务1第23～26题要求从所给的6个选项中为第2～5段每段选择1个正确的小标题2第27～30题要求从所给的6个选项中选择4个正确选项分别完成每个句子 ?????????? ??????????? ????{{B}}Earthquake{{/B}}??1.Everyyear earthquakesareresponsibleforalargenumberofdeathsandavastamountof destructioninvariouspartsoftheworld.Mostofthesedamagingearthquakes occureitherinanarrowbeltwhichsurroundsthePacificOceanorinaline whichextendsfromBurmatotheAlpsinEurope.Someofthedestructionis directlycausedbythequakeitself.Anexampleofthisisthecollapseof buildingsasaresultofthequakeitself.Otherdamageresultsfromland-slides ormajorfireswhichareinitiatedbythequake.??2.Thereare aboutamillionquakesayear.Fortunatelyhowevernotallofthemare destructive.TheintensityofanearthquakeismeasuredontheRichterScale whichgoesfrom0upward.Thehighestscalerecordedtodateis8.9.Major damagegenerallyoccursfromquakesrangingupwardsfrom6.0.??3. Theactualcauseofthequakeitselfisthebreakingofrocksatorbelowthe earth’ssurface.Thisisproducedbypressurewhichscientistsbelievemaybe duetoanumberofreasonstwoofwhicharetheexpansionandcontractionof theearth’scrustandcontinentaldrift.??4.Inordertolimit thedamageandtopreventsomeofthesufferingresultingfromearthquakes scientistsareworkinganwaystoenableaccurateprediction.Special instrumentsareusedtohelppeoplerecordforexampleshakingoftheearth. Scientistsaretryingtofindmethodsthatwillenablethemtoindicatethe exacttimelocationandsizeofanearthquake.??5.Certain phenomenahavebeenobservedwhicharebelievedtobethesignsofimminent earthquakes.Theseincludestrangebehavioursofsomeanimalsthechangesin thecontentofmineralwateretc.Themagneticpropertiesofrocksmayalso displayspecialpatternbeforemajorearthquakeshappen.Scientistshavebeenworkinghardtowarnpeople______.
{{*HTML*}}{{B}}第二篇{{/B}} HiddenSpeciesMayBeSurprisingly Common??Cryptic隐蔽的隐藏的species--animalsthat appearidenticalbutaregeneticallyquitedistant--maybemuchmorewidespread thanpreviouslythought.Thefindingscouldhavemajorimplicationsinareas rangingfrombiodiversity生物多样性estimatesandwildlifemanagementtoour understandingofinfectiousdiseasesandevolution.??Reportsof crypticspecieshaveincreaseddramaticallyoverthepasttwodecadeswiththe adventofrelativelyinexpensiveDNA脱氧核糖核酸sequencingtechnology.Markus PfenningerandKlausSchwenkoftheGoethe-UniversitatinFrankfurtGermany analyzedallknowndataoncrypticanimalspeciesanddiscoveredthattheyare foundinequalproportionsthroughoutallmajorbranchesoftheanimalkingdom andoccurinequalnumbersinallbiogeographical生物地理学的regions.? ?Scientistshadpreviouslyspeculatedthatcrypticspecieswere predominantlyfoundininsectsandreptiles爬行动物andweremorelikelytooccur intropicalratherthantemperate温带的regions.Speciesthatareseemingly widespreadandabundantcouldinrealitybemanydifferentCrypticspeciesthat havelowpopulationsandarehighlyendangeredsaysPfenninger.Untilthe geneticinformationofallspeciesinatleastonetaxon分类单元isthoroughly studiednoonewillknowjusthowmanycrypticspeciesexistItcouldbeas highas30%Pfenningersays.??I’mextremelysurprisedbytheir resultssaysAlexSmithoftheUniversityofGuelphinOntarioCanada.It’s acalltoarmstokeepdoingthebroadkindofgeneticstudiesthatweare doing.??Samplingasmanyindividualsaspossiblescientists hopetocompleteworkonallfishandbirdsinanother5to10years.Once eitherofthesetaxonomicgroupsiscompletedPfenningersaysresearcherswill beabletodecidehowmanycrypticspeciesexistthroughouttheanimal kingdom.??ExamplesofcrypticspeciesincludetheAfrican elephant.A2001studyfoundtheelephantswereactuallytwogenetically distinctnon-interbreeding非杂交繁殖的speciestheAfricanbushelephantandthe Africanelephant.Thespeciesarecurrentlylistedasvulnerableandthreatened respectivelybytheWorldConservationUnionWCU.??The reclassificationsaremorethananacademicexercise.Theydefinepopulations thathaveevolvedindependentlyofeachotherandwhosegeneticdifferencescan havesignificantconsequences.??Intheearly1900s misidentificationofmosquitospeciesbasedonmorphologyconfused:attemptsto controlmalaria疟疾inEurope.Ultimatelywhatwasthoughttobeasingle specieswasactuallymadeupofsixsibling同胞同属speciesonlythreeofwhich transmittedthedisease.Thebasicunitinbiologyisalwaysthespeciesand youhavetoknowwhatyouaredealingwithPfenningersays.Muchprevious researchisnownolongerusedhesaysbecauseitisnotclearwhatspecies wasbeingstudied.Doscientistsknowhowmanycrypticspeciesexist?
Thenewtheorywas{{U}}corroborated{{/U}}.
{{*HTML*}}下面的短文有15处空白请根据短文内容为每处空白确定1个最佳选项 CellPhoneLetsYourSecret Out??Yourcellphoneholdssecretsaboutyou. Besidesthenamesand{{U}}?51?{{/U}}thatyou’veprogrammedintoit tracesofyourDNAlinger逗留onthedeviceaccordingtoanewstudy.? ?DNAisgenetic遗传的materialthat{{U}}?52?{{/U}}ineverycell. LikeyourfingerprintyourDNAisuniquetoyou{{U}}?53?{{/U}}you haveanidenticaltwin.ScientiststodayroutinelyanalyzeDNAinblood saliva涎唾液orhairleft{{U}}?54?{{/U}}atthesceneofacrime.The resultsoftenhelpdetectivesidentify{{U}}?55?{{/U}}andtheir victims.Yourcellphonecanrevealmoreaboutyou{{U}}?56?{{/U}}you mightthink.??MeghanJ.McFaddenascientistatMcMaster UniversityinHamiltonOntarioheardaboutacrimeinwhichthesuspectbled ontoacellphoneandlaterdroppedthe{{U}}?57?{{/U}}Thismadeher wonderwhethertracesofDNAlingeredoncellphones--evenwhennobloodwas involved.{{U}}?58?{{/U}}sheandcolleagueMargaretWallaceofthe CityUniversityofNewYorkanalyzedtheflip-openphones翻盖手机of10 volunteers.Theyusedswabs药签tocollect{{U}}?59?{{/U}}tracesof theusersfromtwopartsofthephone:theoutsidewheretheuserholdsitand the{{U}}?60?{{/U}}whichisplacedattheuser’sear.? ?Thescientistsscrubbed用力擦洗擦净thephonesusingasolutionmademostly {{U}}?61?{{/U}}alcohol.Theaimofwashingwastoremoveall detectabletracesofDNA.Theownersgottheirphones??{{U}} ?62?{{/U}}foranotherweek.Thentheresearcherscollectedthe phonesandrepeatedtheswabbingofeachphoneoncemore.??The scientistsdiscoveredDNAthat{{U}}?63?{{/U}}tothephone’sspeaker oneachofthephones.Bettersampleswerecollectedfromtheoutsideofeach phonebutthoseswabsalsopickedupDNAthatbelongedtootherpeoplewhohad apparentlyalsohandledthephone.{{U}}?64?{{/U}}DNAshowedupeven inswabsthatweretakenimmediatelyafterthephoneswerescrubbed.That suggeststhatwashingwon’tremovealltracesofevidencefromacriminal’s device.Socellphonescannowbeaddedtothe{{U}}?65?{{/U}}ofclues thatcanclinch确定决定acrime-scene investigation.
{{*HTML*}}下面的短文有15处空白请根据短文内容为每处空白确定1个最佳选项 CellPhoneLetsYourSecret Out??Yourcellphoneholdssecretsaboutyou. Besidesthenamesand{{U}}?51?{{/U}}thatyou’veprogrammedintoit tracesofyourDNAlinger逗留onthedeviceaccordingtoanewstudy.? ?DNAisgenetic遗传的materialthat{{U}}?52?{{/U}}ineverycell. LikeyourfingerprintyourDNAisuniquetoyou{{U}}?53?{{/U}}you haveanidenticaltwin.ScientiststodayroutinelyanalyzeDNAinblood saliva涎唾液orhairleft{{U}}?54?{{/U}}atthesceneofacrime.The resultsoftenhelpdetectivesidentify{{U}}?55?{{/U}}andtheir victims.Yourcellphonecanrevealmoreaboutyou{{U}}?56?{{/U}}you mightthink.??MeghanJ.McFaddenascientistatMcMaster UniversityinHamiltonOntarioheardaboutacrimeinwhichthesuspectbled ontoacellphoneandlaterdroppedthe{{U}}?57?{{/U}}Thismadeher wonderwhethertracesofDNAlingeredoncellphones--evenwhennobloodwas involved.{{U}}?58?{{/U}}sheandcolleagueMargaretWallaceofthe CityUniversityofNewYorkanalyzedtheflip-openphones翻盖手机of10 volunteers.Theyusedswabs药签tocollect{{U}}?59?{{/U}}tracesof theusersfromtwopartsofthephone:theoutsidewheretheuserholdsitand the{{U}}?60?{{/U}}whichisplacedattheuser’sear.? ?Thescientistsscrubbed用力擦洗擦净thephonesusingasolutionmademostly {{U}}?61?{{/U}}alcohol.Theaimofwashingwastoremoveall detectabletracesofDNA.Theownersgottheirphones??{{U}} ?62?{{/U}}foranotherweek.Thentheresearcherscollectedthe phonesandrepeatedtheswabbingofeachphoneoncemore.??The scientistsdiscoveredDNAthat{{U}}?63?{{/U}}tothephone’sspeaker oneachofthephones.Bettersampleswerecollectedfromtheoutsideofeach phonebutthoseswabsalsopickedupDNAthatbelongedtootherpeoplewhohad apparentlyalsohandledthephone.{{U}}?64?{{/U}}DNAshowedupeven inswabsthatweretakenimmediatelyafterthephoneswerescrubbed.That suggeststhatwashingwon’tremovealltracesofevidencefromacriminal’s device.Socellphonescannowbeaddedtothe{{U}}?65?{{/U}}ofclues thatcanclinch确定决定acrime-scene investigation.
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