单选题28.Thereason______I'mwritingtoyouistotellyouaboutthepartyonSaturday.

单选题.Thousandsofyearsagomanusedhandyrocksforhissurgicaloperations.Laterheusedsharpbonesorhorns,metalknivesandmorerecently,rubberandplastic.Inthe1960sanewtoolwasdeveloped,onewhichwas,firstofall,tobeofgreatpracticalusetothearmedforcesandindustry,butwhichwasalsotorevolutionizethescienceofsurgery.Thetoolisthelaseranditisbeingusedbymoreandmoresurgeonsallovertheworld.Asweallknow,lightishot,andanysourceoflightwillgivewarmth.Butlightisusuallyspreadoutoverawidearea.Thelightinalaserbeam,however,isconcentrated.Thismeansthatalightwithnomorepowerthanthatproducedbyanordinaryelectriclightbulbbecomesintenselystrongasitisconcentratedtoapinpoint-sizedbeam.Experimentswiththesepinpointbeamsshowedresearchersthatdifferentenergysourcesproducebeamsthathaveaparticulareffectoncertainlivingcells.Itisnowpossibleforeyesurgeonstooperateonthebackofhumaneyeswithoutharmingthefrontoftheeye,simplybypassingalaserbeamrightthroughtheeyeball.Operationswhichonceleftpatientsexhaustedandinneedoflongperiodofrecoverytimenowleavethemfeelingrelaxedandcomfortable.Therapiddevelopmentoflasertechniquesinthepasttenyearshasmadeitclearthatthefutureislikelytobeveryexciting.Perhapssomecancerswillbetreatedwithlasersinawaythatmakessurgerynotonlysaferbutalsomoreeffective.

单选题15.Itisnousejusttellingmetodoit;suggestsome______waystodoit.

单选题 In my mind

单选题.Insomeareasoftheworldtheweatherisvery1andthisfactplaysanimportantpartinthedailylivesofthepeople.2theyarefarmers,fishermen,orsailors,forinstance,they3knowaboutthesechangesaheadoftime.Spacescientistsandairplanepilots4needweather5.6earliesttime,menhave7thesky,tilewind,andtheatmosphere,aswellasavarietyofotherweathersigns,inordertomakeweather8.Butoftentheirweatherpredictionshavenotbeenaccurate.Nowtherearegovernmentbureausinmanyplacesthat9weatherconditionsverycarefully.Theyusealotofscientific10tohelpthemmaketheirforecasts.Forinstance,theyhaveinstrumentsto11speedanddirectionofthewind.Thustheycan12thepathofastorm.Theyhavespecialballoons,ships,andairplanestohelpthem13theiraccuracy,andtheymakeuseofradar,satellitesandcomputerstogather14information.Todaywhenaplane15fromanairport,thepilotcanknowwhatkindofweathertoexpect16hereacheshisdestination(目的地).Ifthereis17rainorsnowinthemountains,aweatherbureaucanpredictthedayand18thehourthatarivermayoverflow(使涨满)itsbanksmanymilesaway.Whenastormismovingina19path,thepeopleinthatareacanlearnofitaheadoftimeand20it.

单选题 Tom's father, as well as his mother

单选题1.Thecoathasa______insidetoshowthetimeandwhereitwasmade.

单选题37.Askilledtennisplayerknowshowto______hiscompetitor'sweaknesssoastogetthefinalvictory.

单选题29.______Iwastryingtodoistopersuademybrothertogiveupsmoking.

单选题1.Peteroftenaccompanieshisparentstotheconcert,______hedoesnotlikeclassicalmusicatall.

单选题13.The20-year-oldtennisplayer'sdreamisto______Chinaat2008BeijingOlympicGames.

单选题57.Thecarpethassomanystainsonitthatitneeds______.

单选题7.Let'sgoonapicnicthisweekend,______?

单选题28.Wemovedtothefrontrow______wecouldhearandseebetter.

单选题.Halfoftheworld'scoralreefs(珊瑚礁)havediedinthelast30years.Nowscientistsareracingtoensurethattherestsurvive.Evenifglobalwarningweretostoprightnow,scientistspredictthatmorethan90%ofcoralswilldieby2050.Ifnomajorstepsaretakentoaddresstheproblem,thereefsmaybeheadedfortotalextinction(灭绝).Theplanet'shealthdependsonthesurvivalofcoralreefs.Theyareoftendescribedas"therainforestsofthesea",becausetheyprovideshelterforawidevarietyofsealife.Inaddition,thereefsserveasbarriersthatprotectcoastlinesfromthefullforceofpowerfulstorms.Coralsareusedinmedicalresearchforcurestodiseases.Theyarekeytolocaleconomiesaswell,sincethereefsattracttourists,thefishingindustry,andotherbusinesses,bringinginbillionsofdollars.Coralsareparticularlysensitivetochangesintemperature.Ariseofjust1to2degreescanforcethecoralstodriveoutthealgae(水藻).Thenthecoralsturnwhiteinaprocesscalled"bleaching".Coralscanrecoverfromshort-termbleaching,butlong-termbleachingcancausepermanentdamage.In1998,whenseasurfacetemperatureswerethehighestinrecordedhistory,coralreefsaroundtheworldsufferedthemostseverebleaching.Itisestimatedthatevenunderthebestofconditions,manyofthesecoralreefswillneeddecadestorecover.Althoughreefsfaceotherthreatsfrompollution,industrialactivities,andoverfishing,itisglobalclimatechangethatmostconcernsscientists.Scientistsremainhopefulthatit'snottoolatetosavethereefs,andsomearemovingaheadonexperimentstoaccomplishthatgoal.

单选题19.Thepolicewereaccusedoffailingto______thepeopleaboutthethreatoftheterrorists.

单选题2.Ithinkyou'dbetterholdyoupositionanddon't______totheirdemands.

单选题24.The______ofmodernlifeinbigcitiesissoquickthatsomeoldpeoplefeelithardtokeepupwithit.