安全监控系统分站应具有如下功能:当掘进工作面或回风流中甲烷浓度() 时,应对局部通风机进行闭锁使之不能启动

A、大于15%CH。
B、大于3%cH
C、小于15NCH。
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正确答案:

B

答案解析:

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Theywillneverreconcilethemselvesto____.

A、defeat
B、theirdefeat
C、bedefeated
D、havetheirdefeat

It’shightimewe_____cuttingdowntherainforests.

A、stopped
B、hadtostop
C、shallstop
D、stop

PARTVREADINGCOMPREHENSION

PASSAGEONE

(1)TheearliestsettlerscametotheNorthAmericancontinenttoestablishcoloniesthatwerefreefromthecontrolsthatexistedinEuropeansocieties.Theywantedtoescapethecontrolsplacedontheirlivesbykingsandgovernments,priestsandchurches,noblemenandaristocrats.ThehistoricdecisionsmadebythosefirstsettlershavehadaprofoundeffectontheshapingoftheAmerican

character.Bylimitingthepowerofthegovernmentandthechurchesandeliminatingaformalaristocracy,theycreatedaclimateoffreedomwheretheemphasiswasontheindividual.IndividualfreedomisprobablythemostbasicofalltheAmericanvalues.Byfreedom,Americansmeanthedesireandtheabilityofallindividualstocontroltheirowndestinywithoutoutsideinterferencefromthegovernment,arulingnobleclass,thechurch,oranyotherorganizedauthority.

(2)Thereis,however,apricetobepaidforthisindividualfreedom:self-reliance.ItmeansthatAmericansbelievetheyshouldstandontheirownfeet,achievingbothfinancialandemotionalindependencefromtheirparentsasearlyaspossible,usuallybyage18or21.

(3)AsecondimportantreasonwhyimmigrantshavetraditionallybeendrawntotheUnitedStatesisthebeliefthateveryonehasaequalchancetoenteraraceandsucceedinthegame.BecausetitlesofnobilitywereforbiddenintheConstitution,noformalclasssystemdevelopedintheU.S.

(4)Thereis,however,apricetobepaidforthisequalityofopportunity:competition.Ifmuchoflifeisseenasrace,thenapersonmustruntheraceinordertosucceed;apersonmustcompetewithothers.ThepressuresofcompetitioninthelifeofanAmericanbegininchildhoodandcontinueuntilretirementfromwork.Infact,anygroupofpeoplewhodoesnotcompetesuccessfullydoesnotfit

intothemainstreamofAmericanlifeaswellasthosewhodo.

(5)AthirdreasonwhyimmigrantshavetraditionallycometotheUnitedStatesistohaveabetterlife.Becauseofitsabundantnaturalresources,theUnitedStatesappearedtobea“landofplentywheremillionscouldcometoseektheirfortunes.Thephrase“goingfromragstoriches”becameasloganfortheAmericandream.Manypeopledidachievematerialsuccess.MaterialwealthbecameavaluetotheAmericanpeople,anditalsobecameanacceptedmeasureofsocialstatus.

(6)Americanspayaprice,however,fortheirmaterialwealth:hardwork.HardworkhasbeenbothnecessaryandrewardingformostAmericansthroughouttheirhistory.Insomeways,materialpossessionsareseenasevidenceofpeople’sabilities.BarryGoldwater,acandidateforthepresidencyin1964,saidthatmostpoorpeoplearepoorbecausetheydeservetobe.MostAmericanswouldfind

thisaharshstatement,butmanymightthinktherewassometruthinit.

(7)ThesebasicvaluesdonottellthewholestoryoftheAmericancharacter.Rather,theyshouldbethoughtofasthemes,aswecontinuetoexploremorefacetsoftheAmericancharacterandhowitaffectslifeintheUnitedStates.

1.Para.4seemstosuggestthat__________.

A.Americansarebornwithasenseofcompetition

B.thepressureofcompetitionbeginswhenonestartswork

C.successfulcompetitionisessentialinAmericansociety

D.competitionresultsinequalityofopportunities

2.WhichofthefollowingmethodsdoestheauthormainlyuseinexplainingAmericanvalues?

A.Comparison

D.Causeandeffect

C.Definition

D.Processanalysis

Ifyouexplainedthesituationtoyoursolicitor,he_____abletoadviseyoumuchbetterthanIcan.

A、wouldbe
B、willhavebeen
C、was
D、were

_____time,he’llmakeafirst-classtennisplayer.

A、Having
B、Given
C、Giving
D、Had
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