执行细胞免疫功能的白细胞是()。
A、巨噬细胞C
暂无解析
Passage2
Questions6to10arebasedonthefollowingpassage:
Whenaluminumwasfirstproducedaboutahundredandfiftyyearsago,itwassodifficulttoseparateformtheoresinwhichitwasfoundthatitspricewashigherthanthatofgold.Thepriceremainedhighuntilanewprocesswasdiscoveredforrefiningthemetalwiththeaidofelectricityapproximatelythreequartersofacenturylater.Thenewmethodwassomuchcheaperthataluminumbecausepracticalformanypurposes,oneofwhichwasmakingpotsandpans.
Aluminumislightweight,rustproofandeasilyshapedintodifferentforms.Bymixingitwithothermetals,scientistshavebeenabletoproduceavarietyofalloys,someofwhichhavethestrengthofsteelbutweighonlyonethirdasmuch.
Today,theusesofaluminumareinnumerable.Perhapsitsmostimportantuseisintransportation.Aluminumisfoundintheengineofautomobiles,inthehullsofboats.Itisalsousedinmanypartsofairplanes.Infact,thehuge“airbus”planeswouldprobablyneverhavebeenproducedifaluminumdidnotexist.Bymakingvehicleslighterinweightaluminumhasgreatlyreducedtheamountoffuelneededtomovethem,Aluminumisalsobeingusedextensivelyinthebuildingindustryinsomecountries.
Sincealuminumissuchaversatile(多用的)metal,itisfortunatethatbauxite(铝土矿),whichisoneofitschiefsources,isalsooneoftheearth’smostplentifulsubstances.Asthesourceofaluminumisalmostinexhaustible,wecanexpectthatmoreandmoreuseswillbefoundforthisversatilemetal.
6.Thepriceofaluminumwassharplyreducedwhenpeoplediscoveredanewrefiningprocesswiththeaidof.
A.windB.solarenergyC.hydraulicpowerD.electricity
7.Aluminumis.
A.lightweight,rustproofbutnoteasilyshapedintodifferentforms
B.heavyweight,rustproofandeasilyshapedintodifferentforms
C.lightweight,rustproofandeasilyshapedintodifferentforms
D.lightweightandeasilyshapedintodifferentformsbutitiseasytobecomerusty
8.WhichofthefollowingisNOTtrue?
A.Aluminumiswidelyusedintransportation.
B.Aluminumisalsousedinmanypartsofairplanes.
C.Aluminumisbeingusedextensivelyinthebuildingindustry.
D.Aluminumisnotusedinitspureform.
9.Aluminumisfoundonearthmostlyintheformof.
A.puremetalB.bauxiteC.goldD.liquid
10.Whatisthepassagetalkingabout?
A.Thefeaturesofaluminumanditsfunctions.B.Theprocessofaluminum.
C.Thediscoveryofaluminum.D.Thepromisingfutureofaluminum.
PartIIICloze
Directions:Therearetwentyblanksinthefollowingpassage.Foreachblanktherearefourchoices.ChoosetheonethatbestfitsintothepassageandthenmarksyouranswerontheAnswerSheet.
Whatmakesachildspeakalanguagehaslongbeenapuzzletolinguists.61speaking,therearetwoschoolsoflinguists,bothofwhomtrytoexplain62achildpicksupalanguagesoeasily.Thefactthatachildpicksalanguage63is64:Atoneyearold,achildisabletosay“bye-bye”;attwo,heisabletousefifty;bytherehebeginsto65tenses.ThefamousAmericanlinguistNoamChomsky66thathumanbeinghaveasortofbuilt-insystemforlanguageuse,andthatthe67is68.Childrenarenottaughtlanguage69theyaretaughtarithmetic.Otherlinguists,70,holdtheviewthatachildlearns71ofhislanguagefromthehintsintheenvironment.72,theoristsofbothschools73thatthereisabiologicalbasisforlanguageuse.The74iswhichismoreimportant,theinnerabilityortheenvironment.Thisiscertainlyafield75tobeexplored.Researchersfrombothschoolsarebusyfindingevidenceto76theirowntheory,but77sideispersuadingtheother.
Itseemsthatinorderto78whyachildlearnsalanguagesoeasily,wehaveto79thejointeffortsofbothschools.Somelinguist,likeDeVilliers,hasrecognizedthevalueofcooperation,and80linguistsofbothsidestoworktogether.
61.A.SurprisinglyB.PersonallyC.ProperlyD.Roughly
62.A.thatB.whenC.whyD.how
63.A.independentlyB.naturallyC.withouthelpD.withease
64.A.confusingB.surprisingC.questionedD.suspected
65.A.masterB.studyC.haveD.get
66.A.doubtsB.believesC.realizesD.criticizes
67.A.helpB.teacherC.environmentD.hint
68.A.quiteessentialB.veryimportantC.notnecessaryD.onlysecondary
69.A.asB.forC.whenD.though
70.A.inparticularB.asaresultC.howeverD.therefore
71.A.alittleB.someC.nothingD.most
72.A.BeforeB.FromnowonC.JustnowD.Bynow
73.A.suspectB.disagreeC.agreeD.realize
74.A.caseB.argumentC.problemD.question
75.A.waitingB.planningC.neverD.unlikely
76.A.provideB.createC.supplyD.support
77.A.notaB.oneC.neitherD.either
78.A.findoutB.ruleoutC.searchforD.lookfor
79.A.getridofB.trustinC.relyonD.persistin
80.A.orderedB.criticizedC.challengedD.urged
Thissickmanwas_____inablanket.
Passage3
Questions11to15arebasedonthefollowingpassage:
About70millionAmericansaretryingtolossweight.Thatisalmost1outofevery3peopleintheUnitedStates.Somepeoplegoonideas.Thismeanstheyeatlesscertainfoods,especiallyfatsandsugars.Otherpeopleexercisewithespecialequipment,takedietpills,orevenhavesurgery.Losingweightishardwork,anditcanalsocostalotofmoney.SowhydosomanypeopleintheUnitedStateswanttoloseweight?
ManypeopleintheUnitedStatesworryaboutnotlookingyoungandattractive.Formanypeople,lookinggoodalsomeansbeingthin.Otherpeopleworryabouttheirhealth.Manydoctorssaybeingoverweightisnothealthy.ButareAmericansreallyfat?Almost30millionAmericansweightatleast20percentmorethantheiridealweight.Infact,theUnitedStateisthemostoverweightcountryinthewild.“ThestoredfatofadultAmericansweight2.3trillionpounds,”saysUniversityofMassachusettsanthropologist(人类学家)GeorgeArmelagos.Hesaysburningoffthatstoredenergywouldproduceenoughpowerfor900,000carstogo12,000miles.
Losingweightishardwork,butmostpeoplewanttofindafastandeasywaytotakeofffat.Bookstoresselllotsofdietbooks.Thesebookstellreadershowtoloseweight.Eachyear,dozensofnewbookslikethesearewritten.Eachoneboaststohelppeopletogetridoffat.
11.WhichofthefollowingisNOTmentionedasawayoflosingweight?
A.Toeatlessfatsandsugars.B.Toworkhard.
12.ManyAmericansaretryingtoloseweightbecause.
A.theywanttolookattractiveB.theyaremisledbydoctors
C.theywanttokeepfitD.bothAandC
13.Thefiguresgiveninthesecondparagraphsuggestthat.
A.AmericansaredependentoncarsB.carsconsumealotofmoney
C.AmericansneedloseweightD.excessoffatcanbeasourceofenergy
14.Itcanbeinferredfromthelastparagraphthat.
A.dietbooksarenotalwayseffectiveB.dietbooksareusuallyhelpful
C.therearelotsofwaysoflosingweightD.bookstoresarekeepingtheirpromises
15.Itcanbeconcludedfromthepassagethat.
A.peoplethinktoomuchoftheirappearance
B.thereisnotasurewayoflosingweightasyet
C.surgeryisthefastestwayoflosingweight
D.goingondietisasafewayoflosingweight
“Whatcoursesareyougoingtodonextsemester”
“Idon’tknow.Butit’sabouttime_____onsomething.”