2024剑桥雅思讲义Table_Completion.docx

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1、ZQ国田IELTSADVANTAGETableCompletionPaSSaHe1ClassesofTreesintheUSAThetimberoftheUnitedStatesisfurnishedbythreewell-definedclassesoftrees:(1)theneedle-leaved,naked-seededconifers,suchaspine,cedar;etc.,(2)thebroad-leavedtreessuchasoak,poplar;etc.,and(3)toaninferiorextentbythe(one-seedleaf)palms,yuccas,an

2、dtheirallies,whichareconfinedtothemostsouthernpartsofthecountry.Broad-leavedtreesarealsoknownasdeciduoustrees,although,especiallyinwarmcountries,manyofthemareevergreen,whiletheneedle-leavedtrees(conifers)arecommonlytermedevergreens,althoughthelarch,baldcypresszandothersshedtheirleaveseveryfall,andev

3、enthenamesbroad-leavedandconiferous,thoughperhapsthemostsatisfactory,arenotatallexact,fortheconiferginkgohasbroadleavesandbearsnocones.Amongthewoodsmen,thewoodsofbroad-leavedtreesareknownashardwoods,thoughpoplarisassoftaspine,andtheconiferouswoodsareknownassoftwoods,notwithstandingthefactthatyewrank

4、shighinhardnessevenwhencomparedwithhardwoods.Bothinthenumberofdifferentkindsoftreesorspeciesandstillmoreintheimportanceoftheirproducttheconifersandbroad-leavedtreesfarexcelthepalmsandtheirrelatives.Inthemanneroftheirgrowth,boththeconifersandbroad-leavedtreesbehavealike,addingeachyearanewlayerofwood,

5、whichcoverstheoldwoodinallpartsofthestemandlimbs.Thus,thetrunkcontinuestogrowinthicknessthroughoutthelifeofthetreebyadditions(annualrings),whichintemperateclimatesare,barringaccidents,accuraterecordsofthetreesage.Withthepalmsandtheirrelativesthestemremainsgenerallyofthesamediameter;thetreeofahundred

6、yearsoldbeingasthickasitwasattenyears,thegrowthofthesebeingonlyatthetop.Evenwhereaperipheralincreasetakesplace,asintheyuccas,thewoodisnotlaidoninwell-definedlayersforthestructureremainsirregularthroughout.Thoughalikeinthemanneroftheirgrowth,andthereforesimilarintheirgeneralmake-up,conifersandbroad-l

7、eavedtreesdiffermarkedlyinthedetailsoftheirstructureandthecharacteroftheirwood.Thewoodofallconifersisverysimpleinitsstructure,thefibrescomposingthemainpartofthewoodallbeingalikeandtheirarrangementregular.Thewoodofthebroad-leavedtreesiscomplexinstructure;itismadeupofdifferentkindsofcellsandfibresandl

8、ackstheregularityofarrangementsonoticeableintheconifers.Thisdifferenceissogreatthatinastudyofwoodstructureitisbesttoconsiderthetwokindsseparately.Inthiscountrythegreatvarietyofwoods,andespeciallyofusefulwoods,oftenmakesthemeredistinctionofthekindorspeciesoftreemostdifficult.Thus,thereareatleasteight

9、pinesofthethirty-fivenativeonesonthemarket,someofwhichsocloselyresembleeachotherintheirminutestructurethatonecanhardlytellthemapartzandyettheydifferinqualityandareoftenmixedorconfoundedinthetrade.Ofthethirty-sixoaks,ofwhichprobablynotlessthansixoreightareQD国IELTSADVANTAGETable Completionmarketed,wec

10、anreadilyrecognizebymeansoftheirminuteanatomyatleasttwotribes-thewhiteandblackoaks.Thesameistrueoftheelevenkindsofhickory,thesixkindsofash,andsoon.ThelistofnamesofalltreesindigenoustotheUnitedStates,asenumeratedbytheUnitedStatesForestService,is495innumber,thedesignationoftreebeingappliedtoallwoodypl

11、antswhichproducenaturallyintheirnativehabitatonemainzerectstem,bearingadefinitecrown,nomatterwhatsizetheyattain.TimberisproducedonlybytheSpermatophyta,orseed-bearingplants,whicharesubdividedintotheGymnosperms(conifers),andAngiosperms(broad-leaved),Theconiferorcone-bearingtree,towhichbelongthepines,l

12、arches,andfirs,isoneofthethreenaturalordersofGymnosperms.Thesearegenerallyclassedassoftwoods,andaremoreextensivelyscatteredandmoregenerallyusedthananyotherclassoftimber;andaresimpleandregularinstructure.Theso-calledhardwoodsareDicotyledonsorbroad-leavedtrees,asubdivisionoftheAngiosperms.Theyaregener

13、allyofslowergrowth,andproducehardertimberthantheconifers,butnotnecessarilyso.Basswood,poplar;sycamore,andsomeofthegums,thoughclassedwiththehardwoods,arenotnearlyashardassomeofthepines.Source:https:WWW.qutenberq.orq/files/26598/26598-h/26598-h.htm#SECTloN/Questions1-6Completethetablebelow.ChooseNOMORETHANONEWORDfromreadingpassage1foreachanswer.TreetypeAlsoknownasWoodknownasDiameterofthetrunkStructureofthewoodBroad-leaved13.Increasesin5whilethetreeisalive6Needle-IeavedConifersor2Coniferouswoodsor4.SimplePalmsRemainsthesame