Unit4SectionA3a4d课件人教版英语八年级下册

(3a-grammarfocus)ofNatureofNatureofNatureTheWondersTheWondersTheWondersSectionAWhatisamazingaboutnature?Unit4Doyouknowwhattheseriversare?TheYellowRiver.TheYangtzeRiver.TheNile.Leadin发源于青藏高原巴颜喀拉山北麓的约古宗列盆地，自西向东流经9个省（自治区），最后在东营市垦利区流入渤海。地理位置黄河是中华文明最主要的发源地，中国人称其为中华民族的“母亲河”。每年都会携带十六亿吨泥沙，其中有十二亿吨流入大海，剩下四亿吨长年留在黄河下游，形成冲积平原，有利于种植。重要性YellowRiver发源于青海省西南部、青藏高原上的唐古拉山脉主峰各拉丹冬雪山，曲折东流，干流先后流经11个省、自治区和直辖市，最后注入东海。地理位置是中国、亚洲第一大河，全球第三长河流。素有中国“黄金水道”之称，通航里程达2800多千米。重要性YangtzeRiver是一条流经非洲东部与北部的河流，与中非地区的刚果河以及西非地区的尼日尔河并列非洲最大的三个河流系统。有两条主要的支流，白尼罗河和青尼罗河。于喀土穆交汇，为尼罗河的干流。穿越11国，最终汇入地中海。地理位置是世界文明发祥地之一，这一地区的人民创造了灿烂的文化，在科学发展的历史长河中做出了杰出的贡献。重要性NileRiverLookandpredictWhat’stheplaceofinterestinthepicture?It’sHukouWaterfallontheYellowRiver.黄河壶口瀑布壶口瀑布（HukouWaterfall）壶口瀑布是黄河干流瀑布，是中国的第二大瀑布，世界上最大的黄色瀑布。黄河奔流至此，两岸石壁峭立，河口收束狭如壶口，故名壶口瀑布。瀑布上游黄河水面宽300米，在不到500米长距离内，被压缩到20—30米的宽度。1000立方米/秒的河水，从20多米高的陡崖上倾注而泻，形成“千里黄河一壶收”的气概。Let’slearn3aListentotheconversationandunderlinethethreeriversmentioned.River_______________________________________YellowRiverYangtzeRiverNileRiverRiverCountryLengthImportanceYellowRiver

_______

___________kmhelpedinthedevelopmentofancient_____________NileRiver

_______

___________kmChinaAfrica5,4646,671civilizations3aReadtheconversationandunderlinethethreeriversmentioned.Yaming:Ella:Welcomeback,Ella!Howwasyourtrip?Itwasgreat!WesawtheHukouWaterfallontheYellowRiver.IsthatthelongestriverinChina?n.

瀑布Yaming:Ella:Yaming:/ˈjæŋtsi/No,theYangtzeRiveristhelongestriverinChina.Ittravelsthefarthestandisabout6,300kilometreslong.TheYellowRiveris5,464kilometreslongandisthesecondlongest.Bytheway,doyouknowwhyit’scalledtheYellowRiver?Becauseit’syellow?Right.Somepartsoftherivercarrybrownandyellowearth.顺便说一下为“Isitbecauseit’syellow?”的省略句，在口语对话中很常见，为了使对话更简洁、快速。（不可数名词）土；泥；泥土Ella:Yaming:That’sinteresting!Ilikelearningaboutrivers.MyfavouriteistheNile.Didyouknowit’sthelongestriverintheworld?Yes,it’s6,67lkilometreslong.It’sveryimportantinEgypt’shistory./ˈiːdʒɪpt/埃及That’sright.BoththeNileandtheYellowRiverhelpedancientcivilizationstodevelop.Andthey’restillveryimportanttoday.Yes.InChina,weevencalltheYellowRiverour“motherriver”!Weshouldprotectthematallcosts.Ella:Yaming:Ella:callsb/sthsth称呼某人/某物为……不惜任何代价=civilizationn.

文明Listentotheconversation.Thenrole-playit.3c

ChecklistStarsSpeakfluentlyandclearly☆☆☆Beautifulpronunciationandtones☆☆☆Facialexpressionsandbodylanguage☆☆☆Fullofemotion☆☆☆、ThelargestgrasslandThelargestdesertThelongestwallHulunbuirGrassland(呼伦贝尔大草原)Ella:CouldyoutellmemoreaboutChina,Yaming?Yaming:

Sure!Whatwouldyouliketoknow?Ella:

What’sthebiggestdesertinChina?Yaming:It’stheTaklimakanDesert.Ella:

Doyouknow...?TaklamakanDesert(塔克拉玛干沙漠)

TheGreatWall(长城)ImaginethatyouareYamingorElla.ContinuetheconversationwithapartneraboutothergeographicalfeaturesinChina.3dReadandsummarizeReadthesentencesandsummarizetherulesforreadinglargenumbers.Itisabout9,000,000squarekilometresinsize.Itisabout11,000metresdeep.TheYangtzeRivertravelsthefarthestinChinaandisabout6,300kilometreslong.大数的表达和读法从数字的右端向左数，每

位数加一个“,”。从右向左，第一个逗号处读

(千)，第二个逗号处

读

(百万)，第三个逗号

处读

(十亿)。三thousandmillionbillionninemillioneleventhousandsixthousandthreehundredTheoceanisabout1,000,000,000squarekilometresinarea.onebillionorabillionReadandsummarizeReadthenumbersandsummarizetherulesforreadinglargenumbers.大数的表达和读法英式英语中，读的时候通常在hundred后加

，如果百位数为0，则在thousand后加

。英语中没有直接表示“万”和“亿”的单位词，而要用thousand和million来表达，如“一万”用“

”、“一亿”用“

”。900,848,300100,thousandmillionbilliononehundredbillion,

ninehundredmillion,eighthundredandforty-eightthousand,threehundredand15,483,034thousandmillionfifteenmillion,

fourhundredandeighty-threethousand,andthirty-fourandtenthousandonehundredmillion、Let’sreadthenumbers!9,613ninethousandsixhundredandthirteen59,613fifty-ninethousandsixhundredandthirteen59,613.78fifty-ninethousandsixhundredandthirteenpointseveneight259,613twohundredandfifty-ninethousandsixhundredandthirteenWriteorspelloutthenumbers.4b1.MountKilimanjaro

is________(fivethousand,eighthundredandninety-five)metreshigh.2.__________(twenty-fivethousand,sevenhundredandsixty-eight)cubicmetresofwaterpoursdownIngaFallseachsecond.3.TheEastAfricanRiftValleyisabout4,000(______________)miles

long.4.TheTaklimakanDeserthasatotalareaofabout337,000(__________________________________)squarekilometres.5,895three

hundred

and

thirty-seven

thousand25,768four

thousand乞力马扎罗山倾泻而下英加瀑布东非大裂谷……总面积为……课本P35GrammarfocusReadthesentences.Circletheadjectiveswhichcomparethings.Underlinetheadverbswhichcompareactions.Whatisthebiggestdesertintheworld?ItistheSaharaDesert.Howbigisit?Itisabout9,000,000squarekilometresinsize.Whereisthedeepestpointintheocean?ItisintheMarianaTrench.Howdeepisit?Itisabout11,000metresdeep.Somedeep-seaanimalsareblind,buttheycan“see”aswellasothers.MountQomolangmaisoneofthegreatestwondersoftheworld,anditisstillgrowingtaller.TheYangtzeRivertravelsthefarthestinChinaandisabout6,300kilometreslong.课本P354aWhatisthebiggestdesertintheworld?Whereisthedeepestpointintheocean?Somedeep-seaanimalsareblind,

buttheycan“see”aswellasothers.MountQomolangmaisoneofthegreatestwondersoftheworld,

anditisstillgrowingtaller.Let’sthink

最高级在对比两者或两者以上的事物时，运用了形容和副词的哪几种形式？原级比较级构成（1）规则变化构成方法示例单音节词和部分双音节词多音节词和部分双音节词low→lower→lowestdeep→deeper→deepestwise→wiser→wisestsimple→simpler→simplestlonely→lonelier→loneliesthappy→happier→happiesthot→hotter→hottestbig→bigger→biggestinteresting→moreinteresting→mostinterestingcarefully→morecarefully→mostcarefully一般情况下，在词尾加-er或-est以字母e结尾的词，在词尾加-r或-st以“辅音字母+y”结尾的词，先把“y”变为“i”，再加-er或-est以一个辅音字母结尾的重读闭音节词，双写该辅音字母，再加-er或-est在词前加more或most（2）不规则变化原级比较级最高级good/wellbad/badly/illlittlemany/muchfarbetterworselessmorefather/furtherbestworstleastmostfarthest/furthestSortthewordsorphrasesintodifferentgroups.Observeandsortbiggestdeepestgreatestaswellastallerfarthest最高级比较级同级最高级的用法形容词与副词的最高级常用于三者或三者以上的人或物之间的比较。常用结构如下：(1)

the+最高级+in/of...……中最……Greenlandisthebiggestislandintheworld.格陵兰岛是世界上最大的岛屿。Who/Which+谓语动词（+the）+最高级，A，BorC?在A、B和C中，谁/哪一个……最……？Whichseasonisthemostbeautiful,spring,summerorautumn?

春天、夏天和秋天中，哪个季节最美？Whojumpshighest,Tom,JimorMike?汤姆、吉姆和迈克中，谁跳得最高？（1）形容词最高级作表语时，the有时可省略。Thismovieis

(the)mostexciting.这部电影最刺激。（2）副词最高级前的the一般可以省略。Lucydances

(the)bestofallthegirls.露西在所有女孩中跳舞跳得最好。Readthesentencesandfillintheblanks.ReadandfillMountQomolangmaisoneofthegreatestwondersoftheworld.最高级结构：oneof+the+形容词

+名词

数。表示“最……的……之一”。最高级复Thislakeistheseconddeepestlakeinthearea.序数词最高级单结构：the+

+形容词

+名词

数。表示“第几最……的……”。Therearesomeerrorsinthesesentences.Readandcorrectthem.JudgeandrewriteTheYangtzeRiverisoneofbiggestriversintheworld.TheNileisoneofthelongestriverintheworld.MountQomolangmaisoneofthehighermountainsintheworld.TheYangtzeRiverisoneofthebiggestriversintheworld.TheNileisoneofthelongestriversintheworld.MountQomolangmaisoneofthehighest

mountainsintheworld.×××Therearesomeerrorsinthesesentences.Readandcorrectthem.JudgeandrewriteK2isthesecondhighermountainintheworld.TheYellowRiverissecondlongestriverinChina.K2isthehighestsecondmountainintheworld.K2isthesecondhighest

mountainintheworld.TheYellowRiveristhesecondlongestriverinChina.K2isthesecondhighest

mountainintheworld.×××Completethepassagewiththecorrectformsofthewordsinthebox.4clargeamazingfarcloseloudMyfriendsandIvisitedVictoria

FallsinAfricalastyear.Visitingoneoftheworld’s_________waterfallswasamagicalexperience.Aswewent_________tothefalls,thenoiseofthewaterslowlygrewlouderand_________.Then,rightbeforeoureyes,thewaterfallappeared.Itwentonforas_