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Many a young scientist ______ engaged in the research work.
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Theinitialfundofgeneralscientificknowledgeisani
Theinitialfundofgeneralscientificknowledgeisan
Theinitialfundofgeneralscientificknowledgeisani
Theyoungscientistdecidedtowork_______inthe_______f
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alone; lonely
alone; alone
lonely; lonely
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Theinitialfundofgeneralscientificknowledgeisani
Hehasmadegreatcontributionstohiscountryandisregard
Thefamousscientistwasgoingout_____hefoundhimselfsu
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while
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Theinitialfundofgeneralscientificknowledgeisani
---______successtheyoungbrilliantscientisthasmadei
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Theinitialfundofgeneralscientificknowledgeisani
Thescientistdid__experimentstotestthenewdrug.
a series of
a good many of
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____severaltimestheyoungscientiststillkeptondoingh
Having failed
Having been failed
Failed
To fail
Theinitialfundofgeneralscientificknowledgeisani
Theinitialfundofgeneralscientificknowledgeisan
Theinitialfundofgeneralscientificknowledgeisani
Manyayoungscientistengagedintheresearchwork.
have
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has been
Theinitialfundofgeneralscientificknowledgeisani
Theinitialfundofgeneralscientificknowledgeisani
.Many___scientistwantstobe__secondNewton.
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Americanpeoplehavealwaysbeenmovingfromoneplacetoanotherthroughoutthehistoryoftheirdevelopment:ThehistoryoftheAmericanpeopleis21thehistoryofthemovementoftheAmericanpeople.TheymovedfromthecoloniesoftheEastCoasttotheopenspaceofthe22.Theymovedfromthecountryandthefarmtothecity.23Americanshavebeenmovingfromthecitiestothesuburbs. PioneerAmericansbegan24fromtheEastCoasttotheWest250yearsago.Theymovedwestformanyreasons.25reasonwasthattheycouldobtain26openspaceandland27farming.Americanslikedlargeopenspacesandtheylikedthefreedomandindependenceto28thelandintheirownway.Someofthelandbecamefarms.Importantmineralswerediscoveredinsomeareassosomeofthelandbecame29.Otherlargeareasbecamefarmsandcattleranches.Thereseemedtobeenoughlandforeverybody.Butitwasadifficultlife--30ofendlessworkandhardship. 24
Heclaimedthathewouldbea______inthepresidentialelectionandwouldwintheelectionatlast.
Stopmakingsomuchnoiseforyouare______meinmystudies.
PassageFour ThefirstEuropeanstockexchangewasestablishedinAntwerpBelgium比利时in1531.TherewerenostockexchangesinEnglanduntilthe1700’s.Amanwishingtobuyorsellsharesofstockhadtofindabrokeragentstotransacthisbusinessforhim.InLondonheusuallywenttoacoffeehousebecausebrokersoftengatheredthere.In1773thebrokersofLondonformedastockexchange. InNewYorkCitybrokersmetunderanoldbutton-woodtreeonWallStreet.TheyorganizedtheNewYorkStockExchangein1792.TheAmericanStockExchangesecondlargestintheUnitedStateswasformerlycalledtheCurbExchangebecauseofitsoriginonthestreetsofNewYorkCity. Astockexchangeisamarketplacewherememberbrokersbuyandsellstocksandbonds债券ofAmericanandforeignbusinessesonbehalfofthepublic.Astockexchangeprovidesamarketplaceforstocksandbondsinthesamewayaboardoftradedoesforcommodities.Thestockbrokersreceiveasmallcommissiononeachtransactiontheymake. Thestockholdermaysellhisstockwhereverhewantstounlessthecorporationhassomespecialruletopreventit.Pricesofstockchangeaccordingtogeneralbusinessconditionsandtheearningsandfutureprospects前景ofthecompany.Ifthebusinessisdoingwellthestockholdermaybeabletosellhisstockforaprofit.Ifitisnothemayhavetotakealoss. Inthe1600'sifamanwantedtobuyorsellsharesofstockhehadtodoitthrough
Theship______frombehindthefog.
A.Thankyouforyourhelp. B.Idon’tthinkIhave. C.That’sOK. D.I’dpreferChinesefood. E.It’seasierthanIthought. F.Heisbusyatthemoment. G.It’sjustonyourleft. H.Butwhy Jack:HaveyoumetMissJonesMary:______
PassageFive OneeveningMr.Greenwasdrivinghomealongalonelycountryroad.Hehad£1000inhispocket.Attheloneliestpartoftheroadamanaskedforalift搭车.Mr.Greentoldhimtogetintothecarandcontinuedhisdriving.WhenhetalkedtothemanandlearnedthatthemanhadbeeninprisonforrobberyandhadbrokenoutofprisontwodaysbeforeMr.Greenwasveryworried. Suddenlyhesawapolice-carandhadabrightidea.Hejustreachedasmalltownwherethespeedlimitwas30milesanhour.Buthedrovethecarasfastasitcouldgo.Helookedbackandsawthatthepolice-carhadbeguntochasehim.Afteramileorsothepolice-carovertook赶上himandorderedhimtostop.ApolicemangotoutandcametoMr.Green’scar.Mr.Greenhopedthathecouldtellthepolicemanabouttheescapedrobberbuthefeltthemanhadputagunagainsthisback.ThepolicemantookouthisnotebookandpencilsayinghewantedMr.Green’snameandaddress.Mr.Greenaskedtobetakentothepolicestationbutthepolicemansaid"Noyouwillhavetoappearatthepolicestationlater."Mr.Greenhadtodoasthepolicemantoldhim.ThepolicemanwrotehisnameandaddressdownputhisnotebookandpencilbackinhispocketandgaveMr.Greenatalkaboutdangerousdriving.ThenMr.Greenstarteduphiscaragainanddroveon. JustashereachedthesuburbofLondonthepassengersaid"Iwanttogetoffhere."Mr.Greenstoppedthecarthemangotoutandsaid"Thanksforthelift.You’yebeengoodtome.ThisistheleastIcandoinreturn."AndhehandedMr.Greenthepoliceman’snotebookwhichhestolewhilethepolicemanwastalkingtoMr.Green. What'stheendofthestory
Let'sthinkofasituation______thisidiomcanbeused.
Americanpeoplehavealwaysbeenmovingfromoneplacetoanotherthroughoutthehistoryoftheirdevelopment:ThehistoryoftheAmericanpeopleis21thehistoryofthemovementoftheAmericanpeople.TheymovedfromthecoloniesoftheEastCoasttotheopenspaceofthe22.Theymovedfromthecountryandthefarmtothecity.23Americanshavebeenmovingfromthecitiestothesuburbs. PioneerAmericansbegan24fromtheEastCoasttotheWest250yearsago.Theymovedwestformanyreasons.25reasonwasthattheycouldobtain26openspaceandland27farming.Americanslikedlargeopenspacesandtheylikedthefreedomandindependenceto28thelandintheirownway.Someofthelandbecamefarms.Importantmineralswerediscoveredinsomeareassosomeofthelandbecame29.Otherlargeareasbecamefarmsandcattleranches.Thereseemedtobeenoughlandforeverybody.Butitwasadifficultlife--30ofendlessworkandhardship. 22
PassageOne Thedoghasalwaysbeenconsideredman’sbestfriend.Alwaysnotedforbeingparticularlyfaithfulinwatchingoverchildrenhealsohashisplacebythefiresideinthecowpastureonthesheeprange放牧区andbesidethehunterinforest.Heiseasytotrainworkshardandoftenperformsastonishingfeats.Andinthefrozenpolarregionshewasoncetheprincipalmotivepowerbeforebeinglatelydisplacedbytheplaneandhelicopter. Becausehehowlsorwhinesinthepresenceofimpendingdeaththedogwasoncethoughttohavesupernaturalpowersandbelievedtobecapableofseeinggodsandghostsinvisibletomen.Actuallythebasisforthesebeliefsliesinthehound’ssensibilitytopeople’sfeelingsandhissuperiorhearingabilityandsenseofsmellwhichenablehimtodetectsignshiddenfromhumanobservation.Hisrecordofsavinglivesisoutstandingforheoftengiveswarningoffireandotherdangersnotnoticedbyhismaster. Thedog’smajorcontributionhoweverhasbeentomedicalresearch.Bothhisdietandhisstructurearecomparabletothoseofthehumanbeingandsohehasbeenthesubjectofcountlessdemonstrationsandexperiments.Open-heartsurgeryhasbeenmadepossiblelargelybecauseofthedog.Buthissacrificehasrepaidhisownspeciesaswellbysafeguardingitfromrabies狂犬病distemperandotherdiseases. Thearticledoesnotsaywhetherthescientists'experimentswithdogshave
PassageFive OneeveningMr.Greenwasdrivinghomealongalonelycountryroad.Hehad£1000inhispocket.Attheloneliestpartoftheroadamanaskedforalift搭车.Mr.Greentoldhimtogetintothecarandcontinuedhisdriving.WhenhetalkedtothemanandlearnedthatthemanhadbeeninprisonforrobberyandhadbrokenoutofprisontwodaysbeforeMr.Greenwasveryworried. Suddenlyhesawapolice-carandhadabrightidea.Hejustreachedasmalltownwherethespeedlimitwas30milesanhour.Buthedrovethecarasfastasitcouldgo.Helookedbackandsawthatthepolice-carhadbeguntochasehim.Afteramileorsothepolice-carovertook赶上himandorderedhimtostop.ApolicemangotoutandcametoMr.Green’scar.Mr.Greenhopedthathecouldtellthepolicemanabouttheescapedrobberbuthefeltthemanhadputagunagainsthisback.ThepolicemantookouthisnotebookandpencilsayinghewantedMr.Green’snameandaddress.Mr.Greenaskedtobetakentothepolicestationbutthepolicemansaid"Noyouwillhavetoappearatthepolicestationlater."Mr.Greenhadtodoasthepolicemantoldhim.ThepolicemanwrotehisnameandaddressdownputhisnotebookandpencilbackinhispocketandgaveMr.Greenatalkaboutdangerousdriving.ThenMr.Greenstarteduphiscaragainanddroveon. JustashereachedthesuburbofLondonthepassengersaid"Iwanttogetoffhere."Mr.Greenstoppedthecarthemangotoutandsaid"Thanksforthelift.You’yebeengoodtome.ThisistheleastIcandoinreturn."AndhehandedMr.Greenthepoliceman’snotebookwhichhestolewhilethepolicemanwastalkingtoMr.Green. Themanaskingforaliftwas
Theforestwas______toafewtreesbythegreatfire.
PassageThree Thereisnocreaturethatdoesnotneedsleeporcompleteresteveryday. Ifyouwanttoknowwhyjusttrygoingwithoutsleepforalongperiodoftime.Youwilldiscoverthatyourmindandbodywouldbecometootiredtoworkproperly.Youwouldbecomeirritableandfindithardtothinkclearlyorconcentrateonyourwork.Sosleepisquitesimplythetimewhenthecellsofyourbodyrecoverfromtheworkofthedayandbuildupsuppliesofenergyforthenextperiodofactivity. Oneofthethingsweallknowaboutsleepisthatweareunconsciousinsleep.Wedonotknowwhatisgoingonaroundus.Butthatdoesn’tmeanthebodystopsallactivity.Theimportantorganscontinuetoworkduringsleepbutmostofthebodyfunctionsaresloweddown. Forexampleourbreathingbecomessloweranddeeper.Theheartbeatsmoreslowlyandthebloodpressureislower.Ourarmsandlegsbecomelimp柔软的andmusclesareatrest.Itwouldbeimpossibleforourbodytorelaxtosuchanextentifwewereawake.Sosleepdoesforuswhatthemostquietrestcannotdo. Yourbodytemperaturebecomeslowerwhenyouareasleepwhichisthereasonpeoplegotosleepundersomekindofcovers.Andeventhoughyouareunconsciousmanyofyourreflexes习惯性思维stillwork.Forinstanceifsomeonetickles使觉得痒yourfootyouwillputitawayinyoursleeporevenbrushaflyfromyourforehead.Youdothesethingswithoutknowingit. Sleephelpsyourbodytorelaxtosuchanextent
Americanpeoplehavealwaysbeenmovingfromoneplacetoanotherthroughoutthehistoryoftheirdevelopment:ThehistoryoftheAmericanpeopleis21thehistoryofthemovementoftheAmericanpeople.TheymovedfromthecoloniesoftheEastCoasttotheopenspaceofthe22.Theymovedfromthecountryandthefarmtothecity.23Americanshavebeenmovingfromthecitiestothesuburbs. PioneerAmericansbegan24fromtheEastCoasttotheWest250yearsago.Theymovedwestformanyreasons.25reasonwasthattheycouldobtain26openspaceandland27farming.Americanslikedlargeopenspacesandtheylikedthefreedomandindependenceto28thelandintheirownway.Someofthelandbecamefarms.Importantmineralswerediscoveredinsomeareassosomeofthelandbecame29.Otherlargeareasbecamefarmsandcattleranches.Thereseemedtobeenoughlandforeverybody.Butitwasadifficultlife--30ofendlessworkandhardship. 30
PassageFour ThefirstEuropeanstockexchangewasestablishedinAntwerpBelgium比利时in1531.TherewerenostockexchangesinEnglanduntilthe1700’s.Amanwishingtobuyorsellsharesofstockhadtofindabrokeragentstotransacthisbusinessforhim.InLondonheusuallywenttoacoffeehousebecausebrokersoftengatheredthere.In1773thebrokersofLondonformedastockexchange. InNewYorkCitybrokersmetunderanoldbutton-woodtreeonWallStreet.TheyorganizedtheNewYorkStockExchangein1792.TheAmericanStockExchangesecondlargestintheUnitedStateswasformerlycalledtheCurbExchangebecauseofitsoriginonthestreetsofNewYorkCity. Astockexchangeisamarketplacewherememberbrokersbuyandsellstocksandbonds债券ofAmericanandforeignbusinessesonbehalfofthepublic.Astockexchangeprovidesamarketplaceforstocksandbondsinthesamewayaboardoftradedoesforcommodities.Thestockbrokersreceiveasmallcommissiononeachtransactiontheymake. Thestockholdermaysellhisstockwhereverhewantstounlessthecorporationhassomespecialruletopreventit.Pricesofstockchangeaccordingtogeneralbusinessconditionsandtheearningsandfutureprospects前景ofthecompany.Ifthebusinessisdoingwellthestockholdermaybeabletosellhisstockforaprofit.Ifitisnothemayhavetotakealoss. Whichofthestatementsistrue
A.but B.duty C.cut D.nut
A.view B.flew C.few D.new
PassageTwo Amongthequestionofdesignconstructionandoperationremainingtobesolvedbeforecommercialairlinerstravelfasterthansoundisthedifficultproblemofsonicboom声震theexplosivesoundgeneratedwhenanobjectmovesthroughtheairatsupersonicspeed超音速. Asoundisapressuredisturbance:asonicboomlikeotherexplosivesoundsistheresultofanabruptchangeinpressure.Anairplaneinsubsonicflightproducesweakchangedinpressurebutbecausethesedisturbancestravelatthespeedofsoundtheymovefasterthantheairplaneandstayinfrontofit.Ineffectthesedisturbanceswarntheairtogetoutofthewayandtheandoesjustjethowevergetsaheadofitsownpressuredisturbances.Consequentlyawaveofsuddenlycompressedair--ashockwave--buildsupandisthrownofflikethewave;hatspreadsfromthebowofaspeedboat. CansonicboomsbeeliminatedTheanswerisacategoricalnegative--theyareaninnerent内在的partofsupersonicflight--butthesonicboomprobablycanbereduced;governmentandprivateresearchisnowunderwaytoimproveunderstandingofthesonicboom.Ifandwhentheboomscanbereducedtotolerablelevelscommercialsupersonictransportscancomerataservice. Researchisunderwayto
体育运动的好处BenefitsofSports
PassageThree Thereisnocreaturethatdoesnotneedsleeporcompleteresteveryday. Ifyouwanttoknowwhyjusttrygoingwithoutsleepforalongperiodoftime.Youwilldiscoverthatyourmindandbodywouldbecometootiredtoworkproperly.Youwouldbecomeirritableandfindithardtothinkclearlyorconcentrateonyourwork.Sosleepisquitesimplythetimewhenthecellsofyourbodyrecoverfromtheworkofthedayandbuildupsuppliesofenergyforthenextperiodofactivity. Oneofthethingsweallknowaboutsleepisthatweareunconsciousinsleep.Wedonotknowwhatisgoingonaroundus.Butthatdoesn’tmeanthebodystopsallactivity.Theimportantorganscontinuetoworkduringsleepbutmostofthebodyfunctionsaresloweddown. Forexampleourbreathingbecomessloweranddeeper.Theheartbeatsmoreslowlyandthebloodpressureislower.Ourarmsandlegsbecomelimp柔软的andmusclesareatrest.Itwouldbeimpossibleforourbodytorelaxtosuchanextentifwewereawake.Sosleepdoesforuswhatthemostquietrestcannotdo. Yourbodytemperaturebecomeslowerwhenyouareasleepwhichisthereasonpeoplegotosleepundersomekindofcovers.Andeventhoughyouareunconsciousmanyofyourreflexes习惯性思维stillwork.Forinstanceifsomeonetickles使觉得痒yourfootyouwillputitawayinyoursleeporevenbrushaflyfromyourforehead.Youdothesethingswithoutknowingit. Whenyouaresleeping
Americanpeoplehavealwaysbeenmovingfromoneplacetoanotherthroughoutthehistoryoftheirdevelopment:ThehistoryoftheAmericanpeopleis21thehistoryofthemovementoftheAmericanpeople.TheymovedfromthecoloniesoftheEastCoasttotheopenspaceofthe22.Theymovedfromthecountryandthefarmtothecity.23Americanshavebeenmovingfromthecitiestothesuburbs. PioneerAmericansbegan24fromtheEastCoasttotheWest250yearsago.Theymovedwestformanyreasons.25reasonwasthattheycouldobtain26openspaceandland27farming.Americanslikedlargeopenspacesandtheylikedthefreedomandindependenceto28thelandintheirownway.Someofthelandbecamefarms.Importantmineralswerediscoveredinsomeareassosomeofthelandbecame29.Otherlargeareasbecamefarmsandcattleranches.Thereseemedtobeenoughlandforeverybody.Butitwasadifficultlife--30ofendlessworkandhardship. 26
PassageOne Thedoghasalwaysbeenconsideredman’sbestfriend.Alwaysnotedforbeingparticularlyfaithfulinwatchingoverchildrenhealsohashisplacebythefiresideinthecowpastureonthesheeprange放牧区andbesidethehunterinforest.Heiseasytotrainworkshardandoftenperformsastonishingfeats.Andinthefrozenpolarregionshewasoncetheprincipalmotivepowerbeforebeinglatelydisplacedbytheplaneandhelicopter. Becausehehowlsorwhinesinthepresenceofimpendingdeaththedogwasoncethoughttohavesupernaturalpowersandbelievedtobecapableofseeinggodsandghostsinvisibletomen.Actuallythebasisforthesebeliefsliesinthehound’ssensibilitytopeople’sfeelingsandhissuperiorhearingabilityandsenseofsmellwhichenablehimtodetectsignshiddenfromhumanobservation.Hisrecordofsavinglivesisoutstandingforheoftengiveswarningoffireandotherdangersnotnoticedbyhismaster. Thedog’smajorcontributionhoweverhasbeentomedicalresearch.Bothhisdietandhisstructurearecomparabletothoseofthehumanbeingandsohehasbeenthesubjectofcountlessdemonstrationsandexperiments.Open-heartsurgeryhasbeenmadepossiblelargelybecauseofthedog.Buthissacrificehasrepaidhisownspeciesaswellbysafeguardingitfromrabies狂犬病distemperandotherdiseases. Inthepolarregionsthedogmainly
PassageTwo Amongthequestionofdesignconstructionandoperationremainingtobesolvedbeforecommercialairlinerstravelfasterthansoundisthedifficultproblemofsonicboom声震theexplosivesoundgeneratedwhenanobjectmovesthroughtheairatsupersonicspeed超音速. Asoundisapressuredisturbance:asonicboomlikeotherexplosivesoundsistheresultofanabruptchangeinpressure.Anairplaneinsubsonicflightproducesweakchangedinpressurebutbecausethesedisturbancestravelatthespeedofsoundtheymovefasterthantheairplaneandstayinfrontofit.Ineffectthesedisturbanceswarntheairtogetoutofthewayandtheandoesjustjethowevergetsaheadofitsownpressuredisturbances.Consequentlyawaveofsuddenlycompressedair--ashockwave--buildsupandisthrownofflikethewave;hatspreadsfromthebowofaspeedboat. CansonicboomsbeeliminatedTheanswerisacategoricalnegative--theyareaninnerent内在的partofsupersonicflight--butthesonicboomprobablycanbereduced;governmentandprivateresearchisnowunderwaytoimproveunderstandingofthesonicboom.Ifandwhentheboomscanbereducedtotolerablelevelscommercialsupersonictransportscancomerataservice. Asonicboomislikeeverysoundinthatitis
A.Thankyouforyourhelp. B.Idon’tthinkIhave. C.That’sOK. D.I’dpreferChinesefood. E.It’seasierthanIthought. F.Heisbusyatthemoment. G.It’sjustonyourleft. H.Butwhy Linda:ExcusemecouldyoushowmehowIcangettothepostofficeJohn:______
Americanpeoplehavealwaysbeenmovingfromoneplacetoanotherthroughoutthehistoryoftheirdevelopment:ThehistoryoftheAmericanpeopleis21thehistoryofthemovementoftheAmericanpeople.TheymovedfromthecoloniesoftheEastCoasttotheopenspaceofthe22.Theymovedfromthecountryandthefarmtothecity.23Americanshavebeenmovingfromthecitiestothesuburbs. PioneerAmericansbegan24fromtheEastCoasttotheWest250yearsago.Theymovedwestformanyreasons.25reasonwasthattheycouldobtain26openspaceandland27farming.Americanslikedlargeopenspacesandtheylikedthefreedomandindependenceto28thelandintheirownway.Someofthelandbecamefarms.Importantmineralswerediscoveredinsomeareassosomeofthelandbecame29.Otherlargeareasbecamefarmsandcattleranches.Thereseemedtobeenoughlandforeverybody.Butitwasadifficultlife--30ofendlessworkandhardship. 28
PassageFive OneeveningMr.Greenwasdrivinghomealongalonelycountryroad.Hehad£1000inhispocket.Attheloneliestpartoftheroadamanaskedforalift搭车.Mr.Greentoldhimtogetintothecarandcontinuedhisdriving.WhenhetalkedtothemanandlearnedthatthemanhadbeeninprisonforrobberyandhadbrokenoutofprisontwodaysbeforeMr.Greenwasveryworried. Suddenlyhesawapolice-carandhadabrightidea.Hejustreachedasmalltownwherethespeedlimitwas30milesanhour.Buthedrovethecarasfastasitcouldgo.Helookedbackandsawthatthepolice-carhadbeguntochasehim.Afteramileorsothepolice-carovertook赶上himandorderedhimtostop.ApolicemangotoutandcametoMr.Green’scar.Mr.Greenhopedthathecouldtellthepolicemanabouttheescapedrobberbuthefeltthemanhadputagunagainsthisback.ThepolicemantookouthisnotebookandpencilsayinghewantedMr.Green’snameandaddress.Mr.Greenaskedtobetakentothepolicestationbutthepolicemansaid"Noyouwillhavetoappearatthepolicestationlater."Mr.Greenhadtodoasthepolicemantoldhim.ThepolicemanwrotehisnameandaddressdownputhisnotebookandpencilbackinhispocketandgaveMr.Greenatalkaboutdangerousdriving.ThenMr.Greenstarteduphiscaragainanddroveon. JustashereachedthesuburbofLondonthepassengersaid"Iwanttogetoffhere."Mr.Greenstoppedthecarthemangotoutandsaid"Thanksforthelift.You’yebeengoodtome.ThisistheleastIcandoinreturn."AndhehandedMr.Greenthepoliceman’snotebookwhichhestolewhilethepolicemanwastalkingtoMr.Green. Mr.Greenwasworriedbecause
Hedidit______gratitudeforeverythingShehaddoneforhim.
PassageTwo Amongthequestionofdesignconstructionandoperationremainingtobesolvedbeforecommercialairlinerstravelfasterthansoundisthedifficultproblemofsonicboom声震theexplosivesoundgeneratedwhenanobjectmovesthroughtheairatsupersonicspeed超音速. Asoundisapressuredisturbance:asonicboomlikeotherexplosivesoundsistheresultofanabruptchangeinpressure.Anairplaneinsubsonicflightproducesweakchangedinpressurebutbecausethesedisturbancestravelatthespeedofsoundtheymovefasterthantheairplaneandstayinfrontofit.Ineffectthesedisturbanceswarntheairtogetoutofthewayandtheandoesjustjethowevergetsaheadofitsownpressuredisturbances.Consequentlyawaveofsuddenlycompressedair--ashockwave--buildsupandisthrownofflikethewave;hatspreadsfromthebowofaspeedboat. CansonicboomsbeeliminatedTheanswerisacategoricalnegative--theyareaninnerent内在的partofsupersonicflight--butthesonicboomprobablycanbereduced;governmentandprivateresearchisnowunderwaytoimproveunderstandingofthesonicboom.Ifandwhentheboomscanbereducedtotolerablelevelscommercialsupersonictransportscancomerataservice. Beforecommercialairlinerstravelfasterthansoundproblemsmust0esolvedregarding
Thegeneralstrikeisameansof______thetotalauthorityofthegovernment.
Welllet'sputourheadstogetherandfindan______totheproblem.
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