Clouds,clouds,cloudsBeforeyoustart(1)and(2)Howmanydifferentkindsofcloudsdoyouknow?Whatdotheylooklikeandwhataretheirnamesinyourlanguage?Canyousometimesseetwoorthreekindsatthesametime?Whatinformationdodifferentkindsofcloudsgiveyouabouttheweather?Reading(1):DescriptionCloudsCloudsoftenlooksoftandfluffy,don'tthey?But,ifyoustoodinacloud,itcertainlywouldn'tfeelsoftandfluffy.Itwouldfeeldamp,asifyouwerestandinginafog.Infactfogisactuallyacloudthatisclosetotheground.Cloudsbringusprecipitation-drizzle,rain,snowandhail.Acloudismadeupofbillionsofwaterdropletsstucktobitsofdustorsalt.Whenthewaterdropletsbecomeheavytheyfallasrain.Ittakesthousandsofthesewaterdropletstoformoneraindropthatisheavyenoughtofalltowardstheground.Highup,theairisverycoldandcloudsareusuallymadeupoftinyiceparticles.Whentheicecrystalsbecomebigger,theyfallassnow.Astheyfallthroughclouds,tinyicecrystalscanalsocollectwaterthatfreezesonthesurfaceoftheicecrystals.Thecrystalsgrowandfalltothegroundashail.Whenyoulookatclouds,youwillnoticethattheyareatdifferentaltitudes.Thesametypeofcloudcanoccuratdifferentaltitudesdependingonwhethertheyareinapolar,temperateortropicalregion.CloudsPolar:altitude(km)Temperate:altitude(km)Tropical:altitude(km)High3-85-136-18Middle2-42-72-8Low0-20-20-2Thethreemaintypesofcloudsarecumuliformclouds,stratiformcloudsoracombinationofthese.Cumuliformcloudslookwoollyandhaveflatbottoms.Stratiformcloudsarelayeredandappearassheetsofcloud.ThenamesofcloudscomefromLatinwordsthatdescribetheircharacteristics.Thewordcumulus(積云)means“heap”socumuluscloudslooklikePilesofrounded，puffyclouds．Thewordstratus(層云)means“spreadout”or“l(fā)ayered”sostratuscloudsarehorizontallayersofcloudsspreadacrossthesky．Thewordcirrus(卷云)means“curlofhair”socirruscloudsarewispylikehairorfeathers．Combinationsofthesenamesareusedtodescribeotherclouds，forexample，cirrocumulus(卷積云)andstratocumulus(層積云)．Ifthewordnimbus(雨云)ornimboisinthename，itmeansthecloudisaraincloud．Ifthewordalto(表示“高”)isinthename．itmeansthecloudsarehigh．(363words／_______minutes)Vocabularyfluffy絨毛狀的precipitation降水(量)drizzle毛毛雨，細雨hail冰雹droplet小滴crystal晶體；水晶polar地極的，極地的temperate溫帶的tropical熱帶的woolly像羊毛的；卷毛的puffy膨脹的，鼓起的wispy一縷縷的，成束的Exercise1TheadjectivesbelowareusedinReading(1)and(2)todescribeclouds.Findtheminthetexts.Guesswhattheymean.Thencheckyourguessesinyourdictionary.fluffy,woolly,wispy,puffy,lumpy,layered,rounded,rippled,striped,horizontalExercise2Answerthesequestions.1.Howisrainformed?2.Howissnowformed?3.Howishailformed?4.Lookatthetable.Whatisthealtituderangeofcloudsintropicalregions?5.Whatclimaticregioncanhighcloudsbeatanaltitudeoffourkilometres?Exercise3LookatthemeaningoftheLatinwordsinthetext.Thenmatchthecloudnamewiththecorrectdescription.1.cumulonimbus(積雨云)2．cirrostratus(卷層云)3．stratocumulus(層積云)4．nimbostratus(雨層云)5．a(chǎn)ltocumulus(高積云)a)raincloudsinhorizontallayersb)rounded,puffycloudshighintheskyc)ahorizontallayerofwispy,feather-likecloudsd)ahorizontallayerofroundedcloudse)raincloudsinaheapReading(2)CloudnameTypeDescriptionWeatherHighcloudscirrus(卷云)SWhite,feathery,wispy,madeupoficecrystals.Don'tbringprecipitation.cirrocumulus(卷積云,魚鱗云)CoLookrippledlikefishscales.Mayprecedethunderstorms.cirrostratus(卷層云)STransparent,whitishcloud,totallyorpartlycoveringthesky.Sometimeswhenthesunorthemoonshinesthroughtheseclouds,weseebrightlycolouredringsaroundthem.Middlecloudsaltocumulus(高積云)CoLooklikewhiteorgrey,puffycottonballs.altostratus(高層云)SGreyorbluish,lightlystriped.Don'tbringprecipitation.nimbostratus(雨層云)SHidethesun,layerofgreycloudsthatdarkenastheirbasesBecomeclosertotheground.Icecrystalsgrowlargeenoughtofallassnow.Thetruerainclouds,bringrainorsnow.Lowcloudsstratus(層云)SLoweststratiformclouds.Looklikegreysheetsspreadacrosssky,blockingoutthesun.Fogsarestratuscloudsthatformonorsinktothesurfaceoftheearth.Don'tbringmuchrainorsnow,morelikelytobringdrizzle.stratocumulus(層積云)CoLumpy-lookingcloud,greyand/orwhitish.Whentheyfilltheskytheyoftenappearinlongheavyridges.Don'tbringprecipitation.cumulus(積云)CLookwoolly,likepilesofcottonballs;theyhaveflatdarkbases.Whensmallormediumandinabluesky,they'refairweatherclouds.Whenbiggeranddarker,rainorsnowisprobablyontheway.Cumulonimbus(積雨云)CFormhugetowersinthesky.Haveflattopsanddarkgreybases.Insidearefiercewinds.Bringthunderstorms.Key:C=cumuliform(積云狀的);S=stratiform(層狀的);Co=combination(混合狀的)Vocabularyrippled呈波紋狀的precede在……之前thunderstorm雷暴transparent透明的lumpy多塊的；高低不平的ridge脊狀突起；山脊tower塔樓，塔fierce猛烈的，狂暴的NotesCottonballs(棉花球)areballsoffluffycottonfromthecottonplantthatpeopleusetocleanorapplylotionstotheskin.Exercise4Readthetableandanswerthequestions.1.Whichcloudsbringprecipitation?2.Whichcloudstellusthatrainmaybeontheway?3.Whichcloudsareacombinationofcumuliformandstratiformclouds?4.Whatisfog?5.Inwhatkindofcloudsmightyouseeringsaroundthemoon?Exercise51.Circlealltheadjectivesinthetablethatdescribetheappearanceofclouds.Usethedictionarytofindthemeaningsofanyyoudon'tknow.2.Canyouthinkofanythingelsethattheseadjectivescoulddescribe?Didyouknow?Aircraftcanformcloudswhenthewaterintheaircraft'sexhaust(噴出氣流)condenses(凝結(jié)).Thesearecalledcondensationtrailsorcontrails(凝跡)Contrailsusuallydisappearintothesurroundingairbutsometimestheyquicklyfreezeandstayintheskyforalongtimeafterthejethaspassed,Thewindmaystretchthemintolongsheetsofnewcirrusclouds.Keys:Exercise21.Whenthewaterdropletsinthecloudsbecomeheavyenoughtofalltothegrou