a rainforest is an area covered by tall trees with the total high rainfall spreading 阅读答案

《a rainforest is an area covered by tall trees with the total high rainfall spreading 阅读答案》由会员上传分享，免费在线阅读，更多相关内容在应用文档-天天文库。

1、Arainforestisanareacoveredbytalltreeswiththetotalhighrainfallspreading阅读答案　　Arainforestisanareacoveredbytalltreeswiththetotalhighrainfallspreadingquiteequallythroughtheyearandthetemperaturerarelydippingbelowl6℃.Rainforestshaveagreateffectontheworldenvironmentbecausetheycantakeinheatfromt

2、hesunandadjusttheclimate.Withouttheforestcover，theseareaswouldreflectmoreheatintotheatmosphere，warmingtherestoftheworld.Losingtherainforestsmayalsoinfluencewindandrainfallpatterns，potentiallycausingcertainnaturaldisastersallovertheworld.　　Inthepasthundredyears，humanshavebegundestroyingra

3、inforestsinsearchofthreemajorresources（资源）：landforcrops，woodforpaperandotherproducts，landforraisingfarmanimals.Thisactionaffectstheenvironmentasawhole.Forexample，alotofcarbondioxide（二氧化碳）intheaircomesfromburningtherainforests.Peopleobviouslyhaveaneedfortheresourceswegainfromcuttingtreesb

4、utwewillsuffermuchmorethanwewillbenefit.　　Therearetwomainreasonsforthis.Firstly，whenpeoplecutdowntrees，generallytheycanonlyusethelandforayearortwo.Secondly，cuttinglargesectionsofrainforestsmayprovideagoodsupplyofwoodrightnow，butinthelongrunitactuallyreducestheworld’swoodsupply.　　Rainfore

5、stsareoftencalledtheworld’sdrugstore.Morethan25％ofthemedicinesweusetodaycomefromplantsinrainforests.However，fewerthanl％ofrainforestplantshavebeenexaminedfortheirmedicalvalue.Itisextremelylikelythatourbestchancetocurediseasesliessomewhereintheworld’sshrinkingrainforests.　　72.Rainforestsca

6、nhelptoadjusttheclimatebecausethey.　　A.reflectmoreheatintotheatmosphere　　B.bringabouthighrainfallthroughouttheworld　　C.rarelycausethetemperaturetodroplowerthanl6℃　　D.reducetheeffectofheatfromthesunontheearth　　【答案】D　　【解析】从第一段第二句话可知答案.　　73.Whatdoestheword“this”underlinedinthethirdparagraph

7、referto?　　A.Wewilllosemuchmorethanwecangain.　　B.Humanshavebegundestroyingrainforests.　　C.Peoplehaveastrongdesireforresources.　　D.Muchcarbondioxidecomesfromburningrainforests.　　【答案】A　　【解析】从第三段后面的叙述中可知人们失去的会比得到的多.　　74.Itcanbeinferredfromthetextthat　　A.wecangetenoughresource