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最新托福考试模拟预测练习题长风破浪会有时,直挂云帆济沧海以下是为大家搜索整理的最新托福考试模拟预测练习题,希望能给大家带来帮助!更多精彩内容请及时关注我们应届毕业生考试网!Themineralparticlesfoundinsoilrangeinsizefrommicroscopicclayparticlestolargeboulders.Themostabundantparticles—sand,silt,andclay—arethefocusofexaminationinstudiesofsoiltexture.Textureisthetermusedtodescribethepositesizesofparticlesinasoilsample,typicallyseveralrepresentativehandfuls.Tomeasuresoiltexture,thesand,silt,andclayparticlesaresortedoutbysizeandweight.Theweightsofeachsizearethenexpressedasapercentageofthesampleweight.lnthefield,soiltexturecanbeestimatedbyextractingahandfulofsoilandsqueezingthedampsoilintothreebasicshapes;lcast,alumpformedbysqueezingasampleinaclenchedfist;2thread,apencilshapeformedbyrollingsoilbetweenthepalms;and3ribbon,aflatfishshapeformedbysqueezingasmallsamplebetweenthethumbandindexfinger.Thebehavioralcharacteristicsofthesoilwhenmoldedintoeachoftheseshapes,iftheycanbeformedatall,providethebasisforageneraltexturalclassification.Thebehaviorofthesoilinthehandtestisdeterminedbytheamountofclayinthesample.Clayparticlesarehighlycohesive,andwhendampened,behaveasaplastic.Thereforethehighertheclaycontentinasample,themorerefinedanddurabletheshapesintowhichitcanbemolded.Anothermethodofdeterminingsoiltextureinvolvestheuseofdevicescalledsedimentsieves,screensbuiltwithaspecifiedmeshsize.Whenthesoilisfilteredthroughagroupofsieves,eachwithadifferentmeshsize,theparticlesbeegroupedincorrespondingsizecategories.Eachcategorycanbeweighedtomakeatexturaldetermination.Althoughsievesworkwellforsilt,sand,andlargerpartides,theyarenotappropriateforclayparticles.Clayisfartoosmalltosieveaccurately;therefore,insoilswithahighproportionofclay,thefineparticlesaremeasuredonthebasisoftheirsettlingvelocitywhensuspendedinwater.Sinceclayssettlesoslowly,theyareeasilysegregatedfromsandandsilt.Thewatercanbedrawnoffandevaporated,leavingaresidueofclay,whichcanbeweighed.l.WhatdoesthepassagemainlydiscussACharacteristicsofhighqualitysoilBParticlestypicallyfoundinmostsoilsCHowahighclaycontentaffectsthetextureofsoilDWaystodeterminethetextureofsoil
2.Theauthormentions,,severalrepresentativehandfulsinline4inordertoshowAtherangeofsoilsamplesBtheprocessbywhichsoilisweighedCtherequirementsforanadequatesoilsampleDhowsmallsoilparticlesareweighted
3.Thephrase,,sortedoutinline5isclosestinmeaningtoAmixedBreplacedCcarriedDseparated
4.ltcanbeinferredthatthenamesofthethreebasicshapesmentionedinparagraph2reflectAthewaythesoilisextractedBtheresultsofsqueezingthesoilCtheneedtocheckmorethanonehandfulDthedifficultyofformingdifferentshapes
5.Theworddampened,,inlinel4isclosestinmeaningtoAdamagedBstretchedCmoistenedDexamined
6.WhichofthefollowingcanbeinferredfromthepassageaboutasoilsamplewithlittleornoclayinitAltisnotveryheavy.Bltmaynotholditsshapewhenmolded.CltsshapeisdurableDltstexturecannotbeclassified
7.Theword,,they,,inline21referstoAcategories筛子BsievesClargerparticles颗粒Dclayparticles
8.ltcanbeinferredfromthepassagethatthesedimentsievehasanadvantageoverthehandtestindeterminingsoiltexturebecauseAusingthesievetakeslesstimeBthesievecanmeasureclayClesstrainingisrequiredtousethesieveDthesieveallowsforamoreexactmeasure
9.Duringtheproceduredescribedinparagraph3,whenclayparticlesareplacedintowaterthey代Asticktothesideso hewatercontainerBtakesometimetosinktothebottomCseparateintodifferentsizesDdissolvequickly
10.Theword,,fine,,inline24isclosestinmeaningto颗粒微小的AtinyBmanyCexcellentDvariousll.AllofthefollowingwordsaredefinedinthepassageEXCEPTAtextureline3BribbonlinelOCsedimentsieveslinel8Devaporatedline25DADBCBBDBAD词汇补充两手都善用的ambidextrous改善ameliorate紫晶amethyst氨苦酸aminacid氨ammonia大量的anarrayof解剖anatomy锚anchor附属的ancillary高血压素angiotensin并吞annex药剂师apothecary吸引力appeal涂apply相当可观的appreciable栖于树木的arboreal拱形建筑物arcade艰:苦的arduous。