【单选题】swimming mAChinEs
tunAs, mACkErEls, AnD BillFishEs (mArlins, sAilFishEs, AnD sworDFish) swim Continuously. FEEDing, Courtship, rEproDuCtion, AnD EvEn "rEst" ArE CArriED out whilE in ConstAnt motion.As A rEsult, prACtiCAlly EvEry AspECt oF thE BoDy Form AnD FunCtion oF thEsE swimming "mAChinEs" is ADAptED to EnhAnCE thEr ABility to swim.
mAny oF thE ADAptAtions oF thEsE FishEs sErvE to rEDuCE wAtEr rEsistAnCE (DrAg). intErEstingly Enough, sEvErAl oF thEsE hyDroDynAmiC ADAptAtions rEsEmBlE FEAturEs DEsignED to improvE thE AEroDynAmiCs oF high-spEED wArCrAFt. though humAn EnginEErs ArE nEw to thE gAmE, tunAs AnD thEir rElAtivEs EvolvED thEr "high-tECh" DEsigns long Ago.
tunAs, mACkErEls, AnD BillFishEs hAvE mADE strEAmlining into An Art For thEir BoDiEs ArE slEEk AnD CompACt. thE BoDy shApEs oF tunAs, in FACt, ArE nEArly iDEAl From An EnginEEring point oF viEw. most spECiEs lACk sCAlEs ovEr most oF thE BoDy, mAking it smooth AnD slippEry. thE EyEs liE Flush with thE BoDy AnD Do not protruDE At All. thEy ArE Also CovErED with A sliCk, trAnspArEnt liD thAt rEDuCEs DrAg. thE Fins ArE stiFF, smooth, AnD nArrow, quAlitiEs thAt Also hElp Cut DrAg. whEn not in usE, thE Fins ArE tuCkED into spECiAl groovEs or DEprEssions so thAt thEy liE Flush with thE BoDy AnD Do not BrEAkup its smooth Contours. AirplAnEs rEtrACt thEir lAnDing gEAr whilE in Flight For thE sAmE rEAson.
tunAs, mACkErEls, AnD BillFishEs hAvE EvEn morE sophistiCAtED ADAptAtions thAn thEsE to improvE thEir hyDroDynAmiCs. thE long Bill oF mArlins, sAilFishEs, AnD sworDFish proBABly hElps thEm slip through thE wAtEr. mAny supErsoniC AirCrAFt hAvE A similAr nEEDlE At thE nosE.
most tunAs AnD BillFishEs hAvE A sEriEs oF kEEls AnD FinlEt nEAr thE tAil.Although most oF thEir sCAlEs hAvE BEEn lost, tunAs AnD mACkErEls rEtAin A pAtCh oF CoArsE sCAlEs nEAr thE hEAD CAllED thE CorsElEt. thE kEEls, FinlEt, AnD CorsElEt hElp DirECt thE Flow oF wAtEr ovEr thE BoDy surFACE in suCh As wAy As to rEDuCE rEsistAnCE (sEE thE FigurE).AgAin, supErsoniC jEts hAvE similAr FEAturEs.
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BECAusE thEy ArE AlwAys swimming, tunAs simply hAvE to opEn thEir mouths AnD wAtEr is ForCED in AnD ovEr thEir gills.
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ACCorDingly, thEy hAvE lost most oF thE musClEs thAt othEr FishEs usE to suCk in wAtEr AnD push it pAst thE gills.
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in FACt, tunAs must swim to BrEAthE.
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thEy must Also kEEp swimming to kEEp From sinking, sinCE most hAvE lArgEly or ComplEtEly lost thE swim BlADDEr, thE gAs FillED sAC thAt hElps most othEr Fish rEmAin BuoyAnt.
onE potEntiAl proBlEm is thAt opEning thE mouth to BrEAthE DEtrACts From thE strEAmlining oF thEsE FishEs AnD tEnDs to slow thEm Down. somE spECiEs oF tunA hAvE spECiAlizED groovEs in thEir tonguE. it is thought thAt thEsE groovEs hElp to ChAnnEl wAtEr through thE mouth AnD out thE gilt slits, thErEBy rEDuCing wAtEr rEsistAnCE.
thErE ArE ADAptAtions thAt inCrEAsE thE Amount oF ForwArD thrust As wEll As thosE thAt rEDuCE DrAg.AgAin, thEsE FishEs ArE thE Envy oF EnginEErs. thErE high, nArrow tAils with swEpt-BACk tips ArE Almost pErFECtly ADAptED to proviDE propulsion with thE lEAst possiBlE EFFort. pErhAps most importAnt oF All to thEsE AnD othEr FAst swimmErs is thEir ABility to sEnsE AnD mAkE usE oF swirls AnD EDDiEs (CirCulAr CurrEnts) in thE wAtEr. thEy CAn gliDE pAst EDDiEs thAt woulD slow thEm Down AnD thEn gAin ExtrA thrust By "pushing oFF" thE EDDiEs. sCiEntists AnD EnginEErs ArE BEginning to stuDy this ABility oF FishEs in thE hopE oF DEsigning morE EFFiCiEnt propulsion systEms For ships.
thE musClEs oF thEsE FishEs AnD thE mEChAnism thAt mAintAins A wArm BoDy
tunAs, mACkErEls, AnD BillFishEs (mArlins, sAilFishEs, AnD sworDFish) swim Continuously. FEEDing, Courtship, rEproDuCtion, AnD EvEn "rEst" ArE CArriED out whilE in ConstAnt motion.As A rEsult, prACtiCAlly EvEry AspECt oF thE BoDy Form AnD FunCtion oF thEsE swimming "mAChinEs" is ADAptED to EnhAnCE thEr ABility to swim.
mAny oF thE ADAptAtions oF thEsE FishEs sErvE to rEDuCE wAtEr rEsistAnCE (DrAg). intErEstingly Enough, sEvErAl oF thEsE hyDroDynAmiC ADAptAtions rEsEmBlE FEAturEs DEsignED to improvE thE AEroDynAmiCs oF high-spEED wArCrAFt. though humAn EnginEErs ArE nEw to thE gAmE, tunAs AnD thEir rElAtivEs EvolvED thEr "high-tECh" DEsigns long Ago.
tunAs, mACkErEls, AnD BillFishEs hAvE mADE strEAmlining into An Art For thEir BoDiEs ArE slEEk AnD CompACt. thE BoDy shApEs oF tunAs, in FACt, ArE nEArly iDEAl From An EnginEEring point oF viEw. most spECiEs lACk sCAlEs ovEr most oF thE BoDy, mAking it smooth AnD slippEry. thE EyEs liE Flush with thE BoDy AnD Do not protruDE At All. thEy ArE Also CovErED with A sliCk, trAnspArEnt liD thAt rEDuCEs DrAg. thE Fins ArE stiFF, smooth, AnD nArrow, quAlitiEs thAt Also hElp Cut DrAg. whEn not in usE, thE Fins ArE tuCkED into spECiAl groovEs or DEprEssions so thAt thEy liE Flush with thE BoDy AnD Do not BrEAkup its smooth Contours. AirplAnEs rEtrACt thEir lAnDing gEAr whilE in Flight For thE sAmE rEAson.
tunAs, mACkErEls, AnD BillFishEs hAvE EvEn morE sophistiCAtED ADAptAtions thAn thEsE to improvE thEir hyDroDynAmiCs. thE long Bill oF mArlins, sAilFishEs, AnD sworDFish proBABly hElps thEm slip through thE wAtEr. mAny supErsoniC AirCrAFt hAvE A similAr nEEDlE At thE nosE.
most tunAs AnD BillFishEs hAvE A sEriEs oF kEEls AnD FinlEt nEAr thE tAil.Although most oF thEir sCAlEs hAvE BEEn lost, tunAs AnD mACkErEls rEtAin A pAtCh oF CoArsE sCAlEs nEAr thE hEAD CAllED thE CorsElEt. thE kEEls, FinlEt, AnD CorsElEt hElp DirECt thE Flow oF wAtEr ovEr thE BoDy surFACE in suCh As wAy As to rEDuCE rEsistAnCE (sEE thE FigurE).AgAin, supErsoniC jEts hAvE similAr FEAturEs.
onE potEntiAl proBlEm is thAt opEning thE mouth to BrEAthE DEtrACts From thE strEAmlining oF thEsE FishEs AnD tEnDs to slow thEm Down. somE spECiEs oF tunA hAvE spECiAlizED groovEs in thEir tonguE. it is thought thAt thEsE groovEs hElp to ChAnnEl wAtEr through thE mouth AnD out thE gilt slits, thErEBy rEDuCing wAtEr rEsistAnCE.
thErE ArE ADAptAtions thAt inCrEAsE thE Amount oF ForwArD thrust As wEll As thosE thAt rEDuCE DrAg.AgAin, thEsE FishEs ArE thE Envy oF EnginEErs. thErE high, nArrow tAils with swEpt-BACk tips ArE Almost pErFECtly ADAptED to proviDE propulsion with thE lEAst possiBlE EFFort. pErhAps most importAnt oF All to thEsE AnD othEr FAst swimmErs is thEir ABility to sEnsE AnD mAkE usE oF swirls AnD EDDiEs (CirCulAr CurrEnts) in thE wAtEr. thEy CAn gliDE pAst EDDiEs thAt woulD slow thEm Down AnD thEn gAin ExtrA thrust By "pushing oFF" thE EDDiEs. sCiEntists AnD EnginEErs ArE BEginning to stuDy this ABility oF FishEs in thE hopE oF DEsigning morE EFFiCiEnt propulsion systEms For ships.
thE musClEs oF thEsE FishEs AnD thE mEChAnism thAt mAintAins A wArm BoDy
【单选题】 (Cameras) of one type or (another) have been (using) for more than (A) hundred years.
A．Cameras
B．another
C．using
D．A
A．Cameras
B．another
C．using
D．A
【单选题】 The word "subjugated" in line 4 is closest in meaning to
A．distinguished
B．segregated
C．Concentrated
D．conquered
A．distinguished
B．segregated
C．Concentrated
D．conquered
【单选题】nEw-AgE trAnsport
it looks As iF it CAmE strAight From thE sEt oF stAr wArs. it hAs Four-whEEl DrivE AnD risEs ABovE roCky surFACEs. it lowErs AnD rAisEs its nosE whEn going up AnD Down hills.AnD whEn it ComEs to A rivEr, it turns AmphiBious: two hyDrojEt powEr it Along By BlAsting wAtEr unDEr its BoDy. thErE is room For two pAssEngErs AnD A DrivEr, who sit insiDE A glAss BuBBlE opErAting ElECtroniC, AirCrAFt-typE Controls.A、vEhiClE so DAring on lAnD AnD wAtEr nEEDs winDsCrEEn wipErs--But it DoEsn’t hAvE Any. wAtEr molECulEs ArE DisintEgrAtED on thE sCrEEn’s surFACE By ultrAsoniC sEnsors.
this unusuAl vEhiClE is thE rACoon. it is An invEntion not oF hollywooD But oF rEnAult, A rAthEr ConsErvAtivE FrEnCh stAtE-ownED CAr-mAkEr, BEttEr known For its FAmily hAtChBACks. rEnAult Built thE rACoon to ExplorE nEw FrEEDoms For DEsignErs AnD EnginEErs CrEAtED By ADvAnCEs in mAtEriAls AnD mAnuFACturing proCEssEs. rEnAult is thinking ABout stArtlingly DiFFErEnt CArs; othEr proDuCErs hAvE rADiCAl nEw iDEAs For trAins, BoAts AnD AEroplAnEs.
thE First oF thE nEw FrEEDoms is in DEsign. powErFul ComputEr-AiDED DEsignCAD、systEms CAn rEplACE with A CliCk oF A ComputEr mousE hours oF lABorious work DonE on thousAnDs oF DrAwing BoArDs. so nEw proDuCts, no mAttEr how CompliCAtED, CAn BE DEvElopED muCh FAstEr. For thE First timE,BoEing will not hAvE to BuilD A giAnt rEpliCA oF its nEw AirlinEr, thE 777, to mAkE surE All thE Bits Fit togEthEr. itsCA
D、systEm will tAkE CArE oF thAt.
But rEnAult is tAkingCA
D、FurthEr. it ClAims thE rACoon is thE worlD’s First vEhiClE to BE DEsignED within thE DigitisED worlD oF virtuAl rEAlity.ComplEx progrAms wErE usED to simulAtE thE vEhiClE AnD thE tErrAin thAt it wAs ExpECtED to Cross. this AllowED A tEAm lED By pAtriCk g. m. lE quémEnt , rEnAult’s inDustriAl-DEsign DirECtor, to "DrivE" it long BEForE A prototypE ExistE
D、
rEnAult is not AlonE in thinking thAt virtuAl rEAlity will trAnsForm AutomotivE DEsign. inDEtroit, ForD is Also invEstigAting its potEntiAl. jACk turnEr, thE Firm’s hEAD oF DEsign, woulD likE DEsignErs in DiFFErEnt pArts oF thE worlD to work morE ClosEly togEthEr, linkED By ComputErs. thEy woulD Do morE thAn stylE CArs. virtuAl rEAlity will Allow EnginEErs to pEEr insiDE thE working pArt oF A vEhiClE.DEsignErs will wAtCh BEAtings movE, oil Flow, gEArs mEsh AnD hyDrAuliCs pump.As thEsE tEChniquEs CAtCh on, EvEn strAngEr vEhiClEs ArE likEly to ComE Along.
trAnsForming thEsE CrEAtions From virtuAl rEAlity to ACtuAl rEAlity will Also BEComE EAsiEr, EspECiAlly with ADvAnCEs in mAtEriAls. Firms thAt onCE BAshED EvErything out oF stEEl now FinD thAt nEw Alloys or CompositE mAtEriAls (whiCh CAn BE mADE From mixturEs oF plAstiC, rEsin, CErAmiCs AnD mEtAls, rEinForCED with FiBrEs suCh As glAss or CArBon) ArE ChAnging thE rulEs oF mAnuFACturing.At thE sAmE timE, olD mAtEriAls kEEp gEtting BEttEr, As thEir proDuCErs try to sECurE thEir plACE in thE FACtory oF thE FuturE.
![]()
this CompEtition is inCrEAsing thE pACE oF DEvElopmEnt oF All mAtEriAls.
![]()
onE CompAny in this FiElD is sCAlEDCompositEs.
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it wAs stArtED in 1982 ByBurr rutAn, An AviAtor who hAs DEvisED mAny unusuAl AirCrAFt.
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it hAs Also workED on CompositE sAils For thEAmEriCA’sCup yACht rACE AnD on gEnErAl motors’ ultrAlitE, A 100-milEs pEr-gAllon ExpErimEntAl FAmily CAr Built From CArBon FiBrE.
AgAin, thE rACoon rEFlECts this rACE BEtwEEn thE olD AnD thE nEw. it usEs ConvEntionAl stEEl AnD whAt rEnAult DEsCriBEs As A nEw "high-limit ElAstiC stEEl" in its ChAssis. this stEEl is 30% lightEr thAn thE usuAl kin
D、thE rACoon Also hAs pArts mADE From C
it looks As iF it CAmE strAight From thE sEt oF stAr wArs. it hAs Four-whEEl DrivE AnD risEs ABovE roCky surFACEs. it lowErs AnD rAisEs its nosE whEn going up AnD Down hills.AnD whEn it ComEs to A rivEr, it turns AmphiBious: two hyDrojEt powEr it Along By BlAsting wAtEr unDEr its BoDy. thErE is room For two pAssEngErs AnD A DrivEr, who sit insiDE A glAss BuBBlE opErAting ElECtroniC, AirCrAFt-typE Controls.A、vEhiClE so DAring on lAnD AnD wAtEr nEEDs winDsCrEEn wipErs--But it DoEsn’t hAvE Any. wAtEr molECulEs ArE DisintEgrAtED on thE sCrEEn’s surFACE By ultrAsoniC sEnsors.
this unusuAl vEhiClE is thE rACoon. it is An invEntion not oF hollywooD But oF rEnAult, A rAthEr ConsErvAtivE FrEnCh stAtE-ownED CAr-mAkEr, BEttEr known For its FAmily hAtChBACks. rEnAult Built thE rACoon to ExplorE nEw FrEEDoms For DEsignErs AnD EnginEErs CrEAtED By ADvAnCEs in mAtEriAls AnD mAnuFACturing proCEssEs. rEnAult is thinking ABout stArtlingly DiFFErEnt CArs; othEr proDuCErs hAvE rADiCAl nEw iDEAs For trAins, BoAts AnD AEroplAnEs.
thE First oF thE nEw FrEEDoms is in DEsign. powErFul ComputEr-AiDED DEsignCAD、systEms CAn rEplACE with A CliCk oF A ComputEr mousE hours oF lABorious work DonE on thousAnDs oF DrAwing BoArDs. so nEw proDuCts, no mAttEr how CompliCAtED, CAn BE DEvElopED muCh FAstEr. For thE First timE,BoEing will not hAvE to BuilD A giAnt rEpliCA oF its nEw AirlinEr, thE 777, to mAkE surE All thE Bits Fit togEthEr. itsCA
D、systEm will tAkE CArE oF thAt.
But rEnAult is tAkingCA
D、FurthEr. it ClAims thE rACoon is thE worlD’s First vEhiClE to BE DEsignED within thE DigitisED worlD oF virtuAl rEAlity.ComplEx progrAms wErE usED to simulAtE thE vEhiClE AnD thE tErrAin thAt it wAs ExpECtED to Cross. this AllowED A tEAm lED By pAtriCk g. m. lE quémEnt , rEnAult’s inDustriAl-DEsign DirECtor, to "DrivE" it long BEForE A prototypE ExistE
D、
rEnAult is not AlonE in thinking thAt virtuAl rEAlity will trAnsForm AutomotivE DEsign. inDEtroit, ForD is Also invEstigAting its potEntiAl. jACk turnEr, thE Firm’s hEAD oF DEsign, woulD likE DEsignErs in DiFFErEnt pArts oF thE worlD to work morE ClosEly togEthEr, linkED By ComputErs. thEy woulD Do morE thAn stylE CArs. virtuAl rEAlity will Allow EnginEErs to pEEr insiDE thE working pArt oF A vEhiClE.DEsignErs will wAtCh BEAtings movE, oil Flow, gEArs mEsh AnD hyDrAuliCs pump.As thEsE tEChniquEs CAtCh on, EvEn strAngEr vEhiClEs ArE likEly to ComE Along.
trAnsForming thEsE CrEAtions From virtuAl rEAlity to ACtuAl rEAlity will Also BEComE EAsiEr, EspECiAlly with ADvAnCEs in mAtEriAls. Firms thAt onCE BAshED EvErything out oF stEEl now FinD thAt nEw Alloys or CompositE mAtEriAls (whiCh CAn BE mADE From mixturEs oF plAstiC, rEsin, CErAmiCs AnD mEtAls, rEinForCED with FiBrEs suCh As glAss or CArBon) ArE ChAnging thE rulEs oF mAnuFACturing.At thE sAmE timE, olD mAtEriAls kEEp gEtting BEttEr, As thEir proDuCErs try to sECurE thEir plACE in thE FACtory oF thE FuturE.
AgAin, thE rACoon rEFlECts this rACE BEtwEEn thE olD AnD thE nEw. it usEs ConvEntionAl stEEl AnD whAt rEnAult DEsCriBEs As A nEw "high-limit ElAstiC stEEl" in its ChAssis. this stEEl is 30% lightEr thAn thE usuAl kin
D、thE rACoon Also hAs pArts mADE From C
【单选题】 The chief justice of the United States presides over the Supreme Court during oral arguments and in conferences ______.
A．(of which decisions concern
B．(have important decisions
C．(that important decisions
D．(concerning important decisions
A．(of which decisions concern
B．(have important decisions
C．(that important decisions
D．(concerning important decisions
【单选题】 What does the passage mainly discuss
A．(Themes commonly found in folk music
B．( Elements that define folk music
C．( Influences of folk music on popular music
D．( The standards of the International Folk Music Council
A．(Themes commonly found in folk music
B．( Elements that define folk music
C．( Influences of folk music on popular music
D．( The standards of the International Folk Music Council
【单选题】 Which of the following can be inferred about the findings described in paragraph 2
A．(Babies who are exposed to more than one language can speak earlier than babies exposed to a single language
B．( Mothers from different cultures speak to their babies in similar ways
C．( Babies ignore facial expressions in comprehending aural language
D．( The mothers observed by the researchers were consciously teaching their babies to speak
A．(Babies who are exposed to more than one language can speak earlier than babies exposed to a single language
B．( Mothers from different cultures speak to their babies in similar ways
C．( Babies ignore facial expressions in comprehending aural language
D．( The mothers observed by the researchers were consciously teaching their babies to speak
【单选题】 According to the passage, which of the following is true about all early domesticated plants
A．( They were varieties of weed
B．(They were moved from disturbed area
C．( They succeeded in areas with many tree
D．( They failed to grow in trampled or damaged area
A．( They were varieties of weed
B．(They were moved from disturbed area
C．( They succeeded in areas with many tree
D．( They failed to grow in trampled or damaged area
【单选题】 The word "depict" in line 2 is closest in meaning to
A．( reorganize
B．( deform
C．( represent
D．( justify
A．( reorganize
B．( deform
C．( represent
D．( justify
【单选题】how Do thE stuDEnts ClAriFy thE BEnEFits AnD DisADvAntAgEs thAt sCiEnCE hAs Brought to us
A、By giving DEFinitions.
B、By Citing ExAmplEs.
C、By oFFEring CAusEs AnD rEsults.
D、By showing sEquEnCEs.
A、By giving DEFinitions.
B、By Citing ExAmplEs.
C、By oFFEring CAusEs AnD rEsults.
D、By showing sEquEnCEs.
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