Unit10Didyouknow?theNile(尼罗河)TheNileisverylong.It’s6673kilometerslong.It’sthe______riverintheworld.longestMountEverest(珠穆朗玛峰)MountEverestisthemountainintheworld.highestsailfish(旗鱼)Thefishisthesailfish.Itcantravelat100kmperhour.fastestbluewhale(蓝鲸)Theanimalisthebluewhale.Itis30metreslongand150tons.biggestgiraffe(长颈鹿)Thegiraffeisthelandanimal.Itis5.5metrestall.tallestThemaninChinais2.36metrestall.tallesttheUSA(美国)TheplaneisintheUSA.Ittravelsat3,530kmperhour.fastestBritain(英国)ThecarisinBritain.Ittravelsat1,020kmperhour.fastestAustralia(澳大利亚)TheboatisinAustralia.Ittravelsat556kmperhour.fastestshortshortertheshortestoldolderoldestWhichisbigger,thepigortheelephant?Theelephantisbigger.Whichistaller,thegiraffeorthedog?Thegiraffeistaller.Whichisfaster,thetigerorthedog?Thetigerisfaster.What’sthesmallestinthepicture?Theantisthesmallest.What’sthebiggestinthepicture?Thewhaleisthebiggest.slowslowerslowestThesnailistheslowest.fastfasterfastestThetigeristhefastest.tall-taller–thetallestshort-shorter–theshortestold–older-theoldestyoung-younger–theyoungestfast-faster—thefastestslow-slower—theslowesttallestshortestoldestyoungestfattestthinnestbiggestsmallestfinefinerfinestthinthinnerthinnesthothotterhottesteasyeasiereasiesthappyhappierhappiest特殊形容词最高级的变化形容词最高级的构成方法:1、一般在形容词末尾加est。如:short---shortest2、一元一辅双写辅,再加est。big---biggest3.以e结尾的,直接加st。如;fine-finest4.以辅音加y结尾的,把y变i,加est。如:happy-happiestHowtallarethey?