【单选题】（） to stand in a warm place, it sours because of the presence of bacteria that convert milk sugar into acid.
A. When milk is allowed
B. When is milk allowed
C. Milk, when allowed
D. When milk allowed
A. When milk is allowed
B. When is milk allowed
C. Milk, when allowed
D. When milk allowed
【单选题】（） industries, inventions, and communal endeavors of the Shakers, the best known is their fine furniture.
A. Of the many
B. Their many
C. Are the many
D. Many of the
A. Of the many
B. Their many
C. Are the many
D. Many of the
【分析解答题】pEtEr CoopEr lAunChED A numBEr oF (suCCEssFul) CommErCiAl (EntErprisE), inCluDing thE CAnton iron works in BAltimorE, (whiCh proDuCED) thE First (CommErCiAlly opErAtED) north AmEriCAn stEAm loComotivE.
【单选题】gADgEts with A sportingChAnCE
ConsumEr ElECtroniCs: nEw sports EquipmEnt, From tEnnis rACkEts to running shoEs, usEs proCEssing powEr to EnhAnCE pErFormAnCE. is thAt FAir why shoulD Aspiring AthlEtEs stAnD on thE siDElinEs whEn A spot oF ElECtroniC AssistAnCE CAn put thEm in thE miDDlE oF thE gAmE thAt is thE quEstion mAny sports-EquipmEnt mAkErs ArE Asking As thEy sEnsE An opportunity to Boost thEir sAlEs with high-tECh proDuCts. you CoulD CAll it thE rEvEngE oF thE nErDs: A nEw wAvE oF miCroChip-EquippED sporting gooDs promisEs to EnhAnCE thE pErFormAnCE oF noviCEs AnD non-sporting typEs AlikE--AnD CoulD EvEn mAkE DiFFiCult sports EAsiEr.
tAkE Cross-Country skiing. viCtor pEtrEnko, An EnginEEr AtDArtmouthCollEgE’s iCE rEsEArCh lAB in nEw hAmpshirE, hAs invEntED somE smArt ski-BrAkEs thAt, hE BEliEvEs, will inCrEAsE thE populArity oF Cross-Country skiing By mAking thE sport lEss ChAllEnging For BEginnErs. thE BrAkEs, CurrEntly BEing tEstED By A ski mAnuFACturEr in thEAlps, oFFEr thE nECEssAry FriCtion For A BiggEr "kiCk-oFF ForCE" AnD mAkE thE skis lEss likEly to sliDE BACkwArDs in thEir trACks. to mAkE this hAppEn, An ElECtriC CurrEnt From thE Bottom oF thE skis pulsEs through thE iCE, mElting A thin lAyEr oF snow thAt instAntly rEFrEEzEs AnD ACts As A sort oF gluE.
this is not thE only Form oF smArt ski to hit thE slopEs.AtomiC, A lEADing ski-mAkEr BAsED inAustriA, plAns to introDuCE A systEm lAtEr this yEAr thAt runs A DiAgnostiC sAFEty ChECk to EnsurE thAt thE ski BinDing is propErly ClosED, with thE rEsult BEing shown on A tiny Built-in liquiD-CrystAl DisplAy. mEAnwhilE, tEnnis EquipmEnt mAnuFACturErs ArE hoping thAt innovAtion will Bring nEw zip to thEir BusinEss As wEll. thEy CErtAinly nEED to Do somEthing: ACCorDing to sportsCAnlnFo, A mArkEt-rEsEArCh Firm BAsED in FloriDA, sAlEs oF tEnnis rACkEts inAmEriCA FEll 12.5% During thE First hAlF oF 2004 CompArED with thE First hAlF oF 2003.
with thE BAll ClEArly in thEir Court, rEsEArChErs At hEAD, A mAkEr oF sporting EquipmEnt, hAvE DEvisED A proDuCt thAt shoulD AppEAl to plAyErs suFFEring From tEnnis ElBow.A、Chip insiDE thE rACkEt Controls piEzo-ElECtriC FiBrEs, whiCh ConvErt mEChAniCAl EnErgy From thE BAll’s impACt into ElECtriCAl potEntiAl EnErgy. this EnErgy is thEn usED to gEnErAtE A CountEr-ForCE in thE piEzo-ElECtriC FiBrEs thAt CAusEs A DAmpEning EFFECt.All oF this, thE Firm sAys, trAnslAtEs into lEss strEss on thE ElBow. hEAD ClAims thAt rEsiDuAl viBrAtions in thE rACkEt ArE DAmpEnED twiCE As FAst As in ConvEntionAl rACkEts, rEDuCing thE shoCk ExpEriEnCED By thE plAyEr’s Arm By morE thAn 50%.
no DouBt purists will oBjECt thAt this is simply not CriCkEt. rulE-mAkErs in mAny sports ArE now BEing ForCED to ConsiDEr thE impliCAtions oF EquipmEnt thAt promisEs to AugmEnt AthlEtEs’ pErFormAnCE with ElECtroniC musClE. thE intErnAtionAl tEnnis FEDErAtion, thAt BoDy is rEsponsiBlE For sEtting thE rulEs oF thE gAmE, hAs spECiFiED in its most rECEnt guiDElinEs thAt "no EnErgy sourCE thAt in Any wAy ChAngEs or AFFECts thE plAying ChArACtEristiCs oF A rACkEt mAy BE Built into or AttAChED to A rACkEt".
yEt DEspitE suCh worDing, thE guiDElinE DoEs not ACtuAlly EliminAtE thE usE oF hEAD’s smArt rACkEts, BECAusE thErE is no ExtErnAl EnErgy sourCE--thE DAmping EFFECt rEliEs solEly on EnErgy From thE BAll’s impACt. though high-tECh EquipmEnt mAy CAusE ControvErsy on thE Court, tEnnis CluBs hAvE to ADhErE to thE guiDElinEs sEt For thE sport, ExplAins stuArt millEr, thE itF’s tEChniCAl mAnAgEr.AnD iF thE rulEs Allow sElF-gEnErAtED ForCEs to moDiFy A rACkEt’s rEsponsE, so BE it.
![]()
DiFFErEnt sports hAvE EnCountErED DiFFErEnt tEChnologiEs, though thE FuturE will unDouBtEDly Bring morE ovErlAp.
![]()
in golF, gADgEts thAt pinpoint thE loCAtion oF thE g
ConsumEr ElECtroniCs: nEw sports EquipmEnt, From tEnnis rACkEts to running shoEs, usEs proCEssing powEr to EnhAnCE pErFormAnCE. is thAt FAir why shoulD Aspiring AthlEtEs stAnD on thE siDElinEs whEn A spot oF ElECtroniC AssistAnCE CAn put thEm in thE miDDlE oF thE gAmE thAt is thE quEstion mAny sports-EquipmEnt mAkErs ArE Asking As thEy sEnsE An opportunity to Boost thEir sAlEs with high-tECh proDuCts. you CoulD CAll it thE rEvEngE oF thE nErDs: A nEw wAvE oF miCroChip-EquippED sporting gooDs promisEs to EnhAnCE thE pErFormAnCE oF noviCEs AnD non-sporting typEs AlikE--AnD CoulD EvEn mAkE DiFFiCult sports EAsiEr.
tAkE Cross-Country skiing. viCtor pEtrEnko, An EnginEEr AtDArtmouthCollEgE’s iCE rEsEArCh lAB in nEw hAmpshirE, hAs invEntED somE smArt ski-BrAkEs thAt, hE BEliEvEs, will inCrEAsE thE populArity oF Cross-Country skiing By mAking thE sport lEss ChAllEnging For BEginnErs. thE BrAkEs, CurrEntly BEing tEstED By A ski mAnuFACturEr in thEAlps, oFFEr thE nECEssAry FriCtion For A BiggEr "kiCk-oFF ForCE" AnD mAkE thE skis lEss likEly to sliDE BACkwArDs in thEir trACks. to mAkE this hAppEn, An ElECtriC CurrEnt From thE Bottom oF thE skis pulsEs through thE iCE, mElting A thin lAyEr oF snow thAt instAntly rEFrEEzEs AnD ACts As A sort oF gluE.
this is not thE only Form oF smArt ski to hit thE slopEs.AtomiC, A lEADing ski-mAkEr BAsED inAustriA, plAns to introDuCE A systEm lAtEr this yEAr thAt runs A DiAgnostiC sAFEty ChECk to EnsurE thAt thE ski BinDing is propErly ClosED, with thE rEsult BEing shown on A tiny Built-in liquiD-CrystAl DisplAy. mEAnwhilE, tEnnis EquipmEnt mAnuFACturErs ArE hoping thAt innovAtion will Bring nEw zip to thEir BusinEss As wEll. thEy CErtAinly nEED to Do somEthing: ACCorDing to sportsCAnlnFo, A mArkEt-rEsEArCh Firm BAsED in FloriDA, sAlEs oF tEnnis rACkEts inAmEriCA FEll 12.5% During thE First hAlF oF 2004 CompArED with thE First hAlF oF 2003.
with thE BAll ClEArly in thEir Court, rEsEArChErs At hEAD, A mAkEr oF sporting EquipmEnt, hAvE DEvisED A proDuCt thAt shoulD AppEAl to plAyErs suFFEring From tEnnis ElBow.A、Chip insiDE thE rACkEt Controls piEzo-ElECtriC FiBrEs, whiCh ConvErt mEChAniCAl EnErgy From thE BAll’s impACt into ElECtriCAl potEntiAl EnErgy. this EnErgy is thEn usED to gEnErAtE A CountEr-ForCE in thE piEzo-ElECtriC FiBrEs thAt CAusEs A DAmpEning EFFECt.All oF this, thE Firm sAys, trAnslAtEs into lEss strEss on thE ElBow. hEAD ClAims thAt rEsiDuAl viBrAtions in thE rACkEt ArE DAmpEnED twiCE As FAst As in ConvEntionAl rACkEts, rEDuCing thE shoCk ExpEriEnCED By thE plAyEr’s Arm By morE thAn 50%.
no DouBt purists will oBjECt thAt this is simply not CriCkEt. rulE-mAkErs in mAny sports ArE now BEing ForCED to ConsiDEr thE impliCAtions oF EquipmEnt thAt promisEs to AugmEnt AthlEtEs’ pErFormAnCE with ElECtroniC musClE. thE intErnAtionAl tEnnis FEDErAtion, thAt BoDy is rEsponsiBlE For sEtting thE rulEs oF thE gAmE, hAs spECiFiED in its most rECEnt guiDElinEs thAt "no EnErgy sourCE thAt in Any wAy ChAngEs or AFFECts thE plAying ChArACtEristiCs oF A rACkEt mAy BE Built into or AttAChED to A rACkEt".
yEt DEspitE suCh worDing, thE guiDElinE DoEs not ACtuAlly EliminAtE thE usE oF hEAD’s smArt rACkEts, BECAusE thErE is no ExtErnAl EnErgy sourCE--thE DAmping EFFECt rEliEs solEly on EnErgy From thE BAll’s impACt. though high-tECh EquipmEnt mAy CAusE ControvErsy on thE Court, tEnnis CluBs hAvE to ADhErE to thE guiDElinEs sEt For thE sport, ExplAins stuArt millEr, thE itF’s tEChniCAl mAnAgEr.AnD iF thE rulEs Allow sElF-gEnErAtED ForCEs to moDiFy A rACkEt’s rEsponsE, so BE it.
【单选题】 Both the United States silver dollar and half-dollar, first minted in 1794, had a figure of Liberty on one side and a eagle on the reverse side.
【单选题】 (During the) first 20 years of the space age, the United States spent (more than) 90billion dollars (onto) its civilian (and) military space programs.
A．During the
B．more than
C．onto
D．and
A．During the
B．more than
C．onto
D．and
【单选题】 Which Of the following terms is defined in the passage
A．( "repertoire" (line 5)
B．( "satire" (line 9)
C．( "additive" (line 19)
D．( "rendering" (line 24)
A．( "repertoire" (line 5)
B．( "satire" (line 9)
C．( "additive" (line 19)
D．( "rendering" (line 24)
【单选题】 The word "accumulated" in line 6 is closest in meaning to
A．( spread out
B．( changed
C．( became denser
D．( built up
A．( spread out
B．( changed
C．( became denser
D．( built up
【单选题】 __________ land and money enabled construction of the Union Pacific railroad to begin from Council Bluffs, Iowa, in 1865.
A．( By the government granting of
B．( Government grants of
C．( For the government to grant
D．( Government grants so that
A．( By the government granting of
B．( Government grants of
C．( For the government to grant
D．( Government grants so that
【单选题】rEADing 1 "ExotiC AnDEnDAngErED spECiEs"
→ whEn you hEAr somEonE BuBBling EnthusiAstiCAlly ABout An ExotiC spECiEs, you CAn sAFEly BEt thE spEAkEr isn’t An ECologist. this is A nAmE For A rEsiDEnt oF An EstABlishED Community thAt wAs DEliBErAtEly or ACCiDEntAlly movED From its homE rAngE AnD BECAmE EstABlishED ElsEwhErE. unlikE most imports, whiCh CAn’t tAkE holD outsiDE thEir homE rAngE, An ExotiC spECiEs pErmAnEntly insinuAtEs itsElF into A nEw Community.
somEtimEs thE ADDitions ArE hArmlEss AnD EvEn hAvE BEnEFiCiAl EFFECts. morE oFtEn, thEy mAkE nAtivE spECiEs EnDAngErED spECiEs, whiCh By DEFinition ArE ExtrEmEly vulnErABlE to ExtinCtion. oF All spECiEs on thE rArE or EnDAngErED lists or thAt rECEntly BECAmE ExtinCt, ClosE to 70 pErCEnt owE thEir prECArious ExistEnCE or DEmisE to DisplACEmEnt By ExotiC spECiEs. two ExAmplEs ArE inCluDED hErE to illustrAtE thE proBlEm.
During thE 1800s,British sEttlErs inAustrAliA just CoulDn’t BonD with thE koAlAs AnD kAngAroos, so thEy stArtED to import FAmiliAr AnimAls From thEir homElAnD、in 1859, in whAt woulD BE thE stArt oF A wholEsAlE DisAstEr, A northErnAustrAliAn lAnDownEr importED AnD thEn rElEAsED two DozEn wilDEuropEAn rABBits (oryCtolAgus CuniCulus). gooD FooD AnD gooD sport hunting—thAt wAs thE iDEA、An iDEAl rABBit hABitAt with no nAturAl prEDAtors wAs thE rEAlity.
six yEArs lAtEr, thE lAnDownEr hAD killED 20,000 rABBits AnD wAs BEsiEgED By 20,000 morE. thE rABBits DisplACED livEstoCk, EvEn kAngAroos. nowAustrAliA hAs 200 to 300 million hippityhopping through thE southErn hAlF oF thE Country. thEy ovErgrAzE pErEnniAl grAssEs in gooD timEs AnD strip BArk From shruBs AnD trEEs During Droughts. you know whErE thEy’vE BEEn; thEy trAnsForm grAsslAnDs AnD shruBlAnDs into EroDED DEsErts. thEy hAvE BEEn shot AnD poisonED、thEir wArrEns hAvE BEEn plowED unDEr, FumigAtED, AnD DynAmitED、EvEn whEn All-out AssAults rEDuCED thEir populAtion sizE By 70 pErCEnt, thE rApiDly rEproDuCing imports mADE A ComEBACk in lEss thAn A yEAr.DiD thE ConstruCtion oF A 2,000-milE-long FEnCE protECt wEstErnAustrAliA no. rABBits mADE it to thE othEr siDE BEForE workErs FinishED thE FEnCE.
→ in 1951, govErnmEnt workErs introDuCED A myxomA virus By wAy oF milDly inFECtED southAmEriCAn rABBits, its normAl hosts. this virus CAusEs myxomAtosis. thE DisEAsE hAs milD EFFECts on southAmEriCAn rABBits thAt CoEvolvED with thE virus But nEArly AlwAys hAD lEthAl EFFECts on o. CuniCulus.Biting insECts, mAinly mosquitoEs AnD FlEAs, quiCkly trAnsmit thE virus From host to host. hAving no CoEvolvED DEFEnsEs AgAinst thE novEl virus, thEEuropEAn rABBits DiED in DrovEs.But, As you might ExpECt, nAturAl sElECtion hAs sinCE FAvorED rApiD growth oF populAtions oF o. CuniCulus rEsistAnt to thE virus.
→ in 1991, on An uninhABitED islAnD in spEnCEr gulF,AustrAliAn rEsEArChErs rElEAsED A populAtion oF rABBits thAt thEy hAD injECtED with A CAlCivirus. thE rABBits DiED quiCkly AnD rElAtivEly pAinlEssly From BlooD Clots in thEir lungs, hEArts, AnD kiDnEys. in 1995, thE tEst virus EsCApED From thE islAnD, possiBly on insECt vECtors. it hAs BEEn killing 80 to 95 pErCEnt oF thE ADult rABBits inAustrAliAn rEgions.At this writing, rEsEArChErs ArE now quEstioning whEthEr thE CAlCivirus shoulD BE usED on A wiDEsprEAD sCAlE, whEthEr it CAn jump BounDAriEs AnD inFECt AnimAls othEr thAn rABBits (suCh As humAns); AnD whAt thE long-tErm ConsEquEnCEs will BE.
A、vinE CAllED kuDzu (puErAriA loBAtA) wAs DEliBErAtEly importED From jApAn to thE unitED stAtEs, whErE it FACEs no sErious thrEAts From hErBivorEs, pAthogEns, or CompEtitor plAnts. in tEmpErAtE pArts oFAsiA, it is A wEll-BEhAvED lEgumE with A wEll-DEvElopED root systEm. it sEEmED likE A gooD iDEA to usE it to Control Erosion on hills AnD highwAy EmBAnkmEnts in thE southEAstErn unitED stAtEs.
![]()
with nothing to stop it, though, ku
→ whEn you hEAr somEonE BuBBling EnthusiAstiCAlly ABout An ExotiC spECiEs, you CAn sAFEly BEt thE spEAkEr isn’t An ECologist. this is A nAmE For A rEsiDEnt oF An EstABlishED Community thAt wAs DEliBErAtEly or ACCiDEntAlly movED From its homE rAngE AnD BECAmE EstABlishED ElsEwhErE. unlikE most imports, whiCh CAn’t tAkE holD outsiDE thEir homE rAngE, An ExotiC spECiEs pErmAnEntly insinuAtEs itsElF into A nEw Community.
somEtimEs thE ADDitions ArE hArmlEss AnD EvEn hAvE BEnEFiCiAl EFFECts. morE oFtEn, thEy mAkE nAtivE spECiEs EnDAngErED spECiEs, whiCh By DEFinition ArE ExtrEmEly vulnErABlE to ExtinCtion. oF All spECiEs on thE rArE or EnDAngErED lists or thAt rECEntly BECAmE ExtinCt, ClosE to 70 pErCEnt owE thEir prECArious ExistEnCE or DEmisE to DisplACEmEnt By ExotiC spECiEs. two ExAmplEs ArE inCluDED hErE to illustrAtE thE proBlEm.
During thE 1800s,British sEttlErs inAustrAliA just CoulDn’t BonD with thE koAlAs AnD kAngAroos, so thEy stArtED to import FAmiliAr AnimAls From thEir homElAnD、in 1859, in whAt woulD BE thE stArt oF A wholEsAlE DisAstEr, A northErnAustrAliAn lAnDownEr importED AnD thEn rElEAsED two DozEn wilDEuropEAn rABBits (oryCtolAgus CuniCulus). gooD FooD AnD gooD sport hunting—thAt wAs thE iDEA、An iDEAl rABBit hABitAt with no nAturAl prEDAtors wAs thE rEAlity.
six yEArs lAtEr, thE lAnDownEr hAD killED 20,000 rABBits AnD wAs BEsiEgED By 20,000 morE. thE rABBits DisplACED livEstoCk, EvEn kAngAroos. nowAustrAliA hAs 200 to 300 million hippityhopping through thE southErn hAlF oF thE Country. thEy ovErgrAzE pErEnniAl grAssEs in gooD timEs AnD strip BArk From shruBs AnD trEEs During Droughts. you know whErE thEy’vE BEEn; thEy trAnsForm grAsslAnDs AnD shruBlAnDs into EroDED DEsErts. thEy hAvE BEEn shot AnD poisonED、thEir wArrEns hAvE BEEn plowED unDEr, FumigAtED, AnD DynAmitED、EvEn whEn All-out AssAults rEDuCED thEir populAtion sizE By 70 pErCEnt, thE rApiDly rEproDuCing imports mADE A ComEBACk in lEss thAn A yEAr.DiD thE ConstruCtion oF A 2,000-milE-long FEnCE protECt wEstErnAustrAliA no. rABBits mADE it to thE othEr siDE BEForE workErs FinishED thE FEnCE.
→ in 1951, govErnmEnt workErs introDuCED A myxomA virus By wAy oF milDly inFECtED southAmEriCAn rABBits, its normAl hosts. this virus CAusEs myxomAtosis. thE DisEAsE hAs milD EFFECts on southAmEriCAn rABBits thAt CoEvolvED with thE virus But nEArly AlwAys hAD lEthAl EFFECts on o. CuniCulus.Biting insECts, mAinly mosquitoEs AnD FlEAs, quiCkly trAnsmit thE virus From host to host. hAving no CoEvolvED DEFEnsEs AgAinst thE novEl virus, thEEuropEAn rABBits DiED in DrovEs.But, As you might ExpECt, nAturAl sElECtion hAs sinCE FAvorED rApiD growth oF populAtions oF o. CuniCulus rEsistAnt to thE virus.
→ in 1991, on An uninhABitED islAnD in spEnCEr gulF,AustrAliAn rEsEArChErs rElEAsED A populAtion oF rABBits thAt thEy hAD injECtED with A CAlCivirus. thE rABBits DiED quiCkly AnD rElAtivEly pAinlEssly From BlooD Clots in thEir lungs, hEArts, AnD kiDnEys. in 1995, thE tEst virus EsCApED From thE islAnD, possiBly on insECt vECtors. it hAs BEEn killing 80 to 95 pErCEnt oF thE ADult rABBits inAustrAliAn rEgions.At this writing, rEsEArChErs ArE now quEstioning whEthEr thE CAlCivirus shoulD BE usED on A wiDEsprEAD sCAlE, whEthEr it CAn jump BounDAriEs AnD inFECt AnimAls othEr thAn rABBits (suCh As humAns); AnD whAt thE long-tErm ConsEquEnCEs will BE.
A、vinE CAllED kuDzu (puErAriA loBAtA) wAs DEliBErAtEly importED From jApAn to thE unitED stAtEs, whErE it FACEs no sErious thrEAts From hErBivorEs, pAthogEns, or CompEtitor plAnts. in tEmpErAtE pArts oFAsiA, it is A wEll-BEhAvED lEgumE with A wEll-DEvElopED root systEm. it sEEmED likE A gooD iDEA to usE it to Control Erosion on hills AnD highwAy EmBAnkmEnts in thE southEAstErn unitED stAtEs.
发布评论 查看全部评论