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1、四级阅读冲刺训练 Someplantsgetsohungrytheyeatflies,spiders,andevensmallfrogs.What'smoreamazingisthattheseplantsoccurnaturally（inspecialenvironments）ineverystate.Infact,they'refoundoneverycontinentexceptAntarctica. You'veprobablyseenaVenus'flytrap.It'softensoldinmu
2、seumgiftstores,departmentstores,andevensupermarkets.Asmallplant,itgrows6to8inchestallinacontainer.Attheendofitsstalks（茎）arespeciallymodifiedleavesthatactliketraps.Insideeachtrapisaliningoftinytrigger（触发）hairs.Whenaninsectlandsonthem,thetrapsuddenlyshut.Overt
3、hecourseofaweekorso,theplantfeedsonitscatch. TheVenus'flytrapisjustoneofmorethan500speciesofmeat-eatingplants,saysBarryMeyers-Rice,theeditoroftheInternationalCarnivorousPlantSociety'sNewsletter.Note:Despiteanyscience-fictionstories（科幻小说）youmighthaveread,nom
4、eat-eatingplantdoesanydangertohumans. Dr.Meyers-Ricesaysaplantismeat-eating,onlyifitdoesallfourofthefollowing:"attract,kill,digest,andabsorb"someformofinsects,includingflies,butterflies,andmoths.Meat-eatingplantslookandactlikeothergreenplants—well,mostofthe
5、time. Allgreenplantsmakesugarthroughaprocesscalledphotosynthesis（光合作用）.Plantsusethesugartomakefood.Whatmakes"meat-eating"plantsdifferentistheirbug-catchingleaves.Theyneedinsectsforonereason:nitrogen（氮）.Nitrogenisanutrientthattheycan'tobtainanyotherway.WhyAl
6、mostallgreenplantsonourplanetgetnitrogenfromthesoil"Meat-eating"plantscan't.Theyliveinplaceswherenutrientsarehardoralmostimpossibletogetfromthesoilbecauseofitsacidity（酸度）.Sothey'vecometorelyongettingnitrogenfrominsectsandsmallanimals.Infact,nutrient-richsoil
7、ispoisonousto"meat-eating"plants.Neverfertilize（施肥）them!Butdon'tworry,either,iftheyneverseemtocatchanyinsects.Theycansurvive,butthey'llgrowveryslowly. Questions1to5arebasedonthepassageabove. 1.Accordingtothepassage,carnivorousplants_____. A.onlygrowinwild
8、filed B.areraretosee C.areascommonasflies D.cannotgrowonAntarctica 2.Venus'flytrappreysoninsectsby_____. A.itsnumerouselongatedstalks B.acontainerwhereitgrows C.itsinsect-catchingleaves
