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1、I」阅读理解A（2018•广西重点高中二模）Peoplelovecellphones,whichiswhyninetenAmericansownone.Butdoesheavyuseofcellphonesposeariskofcancer?Thisquestionhascausedcontroversyformanyyears・Anewstudyinratsnowaugmentsthoseconcerns・Itsdatalinkedlong-term,intenseexposuretoradiationfromcel
2、lphoneswithanincreasedriskofcancerintheheartorbrain.Theresultshaveyettobeconfirmed,theauthorsnote・Indeed,althoughtheratstudyfoundalinkbetweencellphoneradiationandcancer,itoffersnocluestowhysuchalinkmightexist,notesJonathanSamet.Heteachespreventativemedicineanddi
3、rectstheInstituteforGlobalHealthattheUniversityofSouthernCaliforniainLosAngeles・Still,hecallsthenewstudy'sfindings^significant^・Theycouldleadtostudiesresearchinghowcellphoneradiationmightcausecancer,hesays.Phonesignalsarerelayedbetweencelltowersandcellphonesviar
4、adiowaves・Thisradiofrequency一orRF一radiationisatypeknownasnomionizing（非电离的）.UnlikeX-rays,non-ionizingradiationdoesnotdepositenoughenergyintocellstoreleaseelectronsfromatomsormolecules,producingions・Soittendstobefarlessharmfulthanionizingradiation,suchasX-rays.But
5、thatdoesnotmeanradiowavesmightnotcauseharm.Inverylargedoses（量）thisradiationwillheatthebodyandcausetissuedamage・Butit'snotyetknownwhatmuchlowerRFlevelsmightdo,suchasthosefromcellphoneuse.Fiveyearsago,theWorldHealthOrganization^InternationalAgencyforResearchonCanc
6、er,orIARC,concludedthatcellphoneuse“ispossiblycarcinogenic（致癌的）”・Itsconclusionwasbasedonwhatlitlleresearchdatawasavailableatthattime.ButnoticethatIARCwasnotcertain.Itsaidonlythatphoneusemight“possibly"causecancer.SoscientistsattheNationalToxicologyProgram,orNTP,
7、investigatedfurther.【文章大意】本文是一篇说明文。人们喜欢用手机，90%的美国人都有手机。那么，过度使用手机是否会有患癌的风险呢？一项新的研究给出了一些线索。【难句分析】Indeed,althoughtheratstudyfoundalinkbetweencellphoneradiationandcancer,itoffersnocluestowhysuchalinkmightexist,notesJonathanSamet・分析：本句为复合句oalthough引导让步状语从句owhysuchali
8、nkmightexist为why引导的宾语从句,作介词to的宾语。译文：JonathanSamet指出，事实上，尽管在老鼠身上进行的研究发现手机辐射和癌症之间有联系，但却没有提供线索表明这种联系为什么可能存在。1・Whichofthefollowingcanreplacetheunderlinedword"augments”?A.
