托福阅读理解试题.docx

托福阅读理解试题

托福阅读理解试题 引言:面对即将到来的托福考试正在苦心备战的小伙伴看过来!小编给大家带来了真题强化训练，以便帮助你们更好地展开复习工作。如想了解更多内容请关注应届毕业生网! 托福阅读原文 GroundwateristhewordGroundwateristhewordusedtodescribewaterthatsaturatestheground,fillingalltheGroundwateristhewordusedtodescribewaterthatsaturatestheground,fillingalltheavailablespaces.Byfarthemostabundanttypeofgroundwaterismeteoricwater;thisisthegroundwaterthatcirculatesaspartofthewatercycle.Ordinarymeteoricwateriswaterthathassoakedintothegroundfromthesurface,fromprecipitation(rainandsnow)andfromlakesandstreams.Thereitremains,sometimesforlongperiods,beforeemergingatthesurfaceagain.Atfirstthoughtitseemsincrediblethattherecanbeenoughspaceinthe“solid”groundunderfoottoholdallthiswater. Thenecessaryspaceisthere,however,inmanyforms.Thecommonestspacesarethoseamongtheparticles—sandgrainsandtinypebbles—ofloose,unconsolidatedsandandgravel.Bedsofthismaterial,outofsightbeneaththesoil,arecommon.Theyarefoundwhereverfastriverscarryingloadsofcoarsesedimentonceflowed.Forexample,asthegreaticesheetsthatcoveredNorthAmericaduringthelasticeagesteadilymeltedaway,hugevolumesofwaterflowedfromthem.Thewaterwasalwaysladenwithpebbles,gravel,andsand,knownasglacialoutwash,thatwasdepositedastheflowsloweddown. Thesamethinghappenstothisday,thoughonasmallerscale,whereverasediment-ladenriverorstreamemergesfromamountainvalleyontorelativelyflatland,droppingitsloadasthecurrentslows:thewaterusuallyspreadsoutfanwise,depositingthesedimentintheformofasmooth,fan-shapedslope.Sedimentsarealsodroppedwhereariverslowsonenteringalakeorthesea,thedepositedsedimentsareonalakefloorortheseaflooratfirst,butwillbelocatedinlandatsomefuturedate,whenthesealevelfallsorthelandrises;suchbedsaresometimesthousandsofmetersthick. Inlowlandcountryalmostanyspotonthegroundmayoverliewhatwasoncethebedofariverthathassincebecomeburiedbysoil;iftheyarenowbelowthewater’suppersurface(thewatertable),thegravelsandsandsoftheformerriverbed,anditssandbars,willbesaturatedwithgroundwater. Somuchforunconsolidatedsedi