YI.阅读理解(2015•江西)Todaytherearemanymorefiresthaninthepast.Over100000wildfiresburneachyearinAmerica.Russiahas20000to35000wildfireseveryyear.Australiahasonaverage60000eachyear.TheseHresdestroy(损

　　YI.阅读理解(2015•江西)Todaytherearemanymorefiresthaninthepast. Over100000wildfiresburneachyearinAmerica.Russiahas20000to35000wildfireseveryyear.Australiahasonaverage60000eachyear.TheseHresdestroy(损害)hugeareasofforestsandburnhundredsofhomes.

　　Manyexpertsbelievethereareseveralreasonsforthissuddenincreaseinfires.Thefirstreasonisclimate(气候)change.Recentweatherhasbeenwarmeranddrier.Thisleadstodangerousfireconditions.Whenlightningstrikes(发生雷电)，drygrasseasilycatchesfire.Hotwindsaddtotheproblem.Thewindspreadsafirequickly.In2010Russiahadthehottestanddriestsummerinacentury. Injustonemonth500firesdestroyedover2000homes.Somepeoplelosttheirlives.

　　Traditionalfire-fightingpracticesareanotherreasonfortheincreaseinfires.InAmericafirefightersusedtoquicklyputouteveryfire.Theydidn'tallowthegrassandtreestoburn.Asaresulttodaymanyforestshavethickervegetation(植被). Thickervegetationmeansmorefuel(燃料)forfires. Alsowithoutfiresfromtimetotimeforestsbecomeovercrowdedandunhealthy.Sometreesaredead.Thedeadwoodtheneasilycatchesfire.SosurprisinglyAmericahasmanymorefirestodaypartlybecauseofitspastfire-fightingpractices.

　　Scientistsnowunderstandthatafirecanbeanaturalpartofahealthyforest.AsaresultcountrieslikeAustraliaallowmorefirestoburnnaturally. Sometimesfirefightersevenstartfirestogetridof(去除)deadwood.Ofcoursetheycarefullycontrolthefires. Thefirethinsoutoldtrees.Thisallowssunlighttoreachtheground.Asaresultfireshelpnewtreestogrow. Thereforeifafireisnotaserious threat(威胁)topeoplefirefightersmayletitburnnaturally.

　　1.WhydidRussiahavesomanyfiresinonemonthin2010?

　　   A.Becauselightningspreadthefire.

　　   B.Becausetherewasmuchfuelforfires.

　　   C.Becausetherewerenotenoughfirefighters.

　　   D.Becauseitwasunusuallyhotdryandwindy.

　　2.WhathappensbecauseofthetraditionalfirefightingpracticesintheUSA?

　　   A.Therearefewerwildfires.

　　   B.Treesandgrassbecomethicker.

　　   C.Theweatherbecomeswarmeranddrier.

　　   D.Sunl