Unit7ThenaturalworldReading1课件译林版八年级英语上册

Unit7ThenaturalworldReading11.Masterthepronunciationandmeaningofkeywordssuchasecosystem,pollution,andoxygen.2.Beabletograspthemainideaofthepassagebyskimmingandextractkeyinformationbyscanning.3.BeabletodiscussandexpressideasrelatedtoecosystemsinEnglish.LearningobjectivesCanyousharesomefunfacts

about

ecosystems?RevisionHowmanyecosystemsarethereinthevideo?LeadinTheyareOceansWetlandsandForestsLet'sexplorethethreemagiclandsoftheEarth—oceans,wetlandsandforests.Whatdoyouknowaboutoaceans,wetlands

andforests?Thebigthree:oceans,wetlandsand

forestsAn

ecosystem

includes

allthe

living

andnon-livingthings

in

an

area.Ecosystemscanbeof

differentsizes,fromsmallpondstolarge

grasslands.Eachecosystemhasaroletoplayand

helps

keep

the

balance

between

all

its

members

and

the

greater

environment.Theocean

is

a

very

large

ecosystemon

earth.It

covers

around71%of

theearth's

surface

andproduces

about

70%of

the

earth's

oxygen.It

holds

plenty

ofsaltwater,andthe

water

rises

to

the

sky,falls

onto

the

land

and

then

returns

tothe

ocean.This

goes

on

and

on,so

the

ocean

isjust

like

the“heart”oftheEarth.Wetlands

only

cover

about

6%ofthe

earth's

land

area.But

they

are

home

to

about

40%of

the

world's

plants

andanimals.Plants

in

wetlands

help

get

ridofpollution

and

make

the

water

clean.Wetlands

can

also

help

prevent

floods.During

heavy

rains,wetlandsstore

water

like

giant

sponges.They

act

like

the"kidneys"ofthe

earth.Forests

make

up

nearly

a

third

ofthe

earth's

landarea.Plants

there

take

in

carbon

dioxide

from

the

air

and

produce

oxygen.They

also

trap

harmful

things

in

their

leaves

and

help

clean

the

air.

Therefore,people

often

call

forests

the"lungs"of

the

earth.Each

ofthese

ecosystems

supports

millions

ofplants

andanimals.They

keep

the

planet

healthy

and

make

our

world

a

better

place.Readthetextandcompletethefollowingtasks.Task1Whatisanecosystem?Anecosystemincludesallthe

(plants,animals,microorganisms)and_______________

(water,air,soil,sunlight)inanarea,andtheyworktogethertokeepbalance.livingthingsnon-livingthingsTask2Whatarethethreemainecosystemsmentioned?Whataretheirnicknames?Thethreemainecosystemsmentionedare

oceans,

wetlands,and

forests.Oceansarenicknamedthe"heart"oftheearth.Wetlandsarenicknamedthe"kidneys"oftheearth.Forestsarenicknamedthe"lungs"oftheearth.Task3Howbigarethey?WhatcantheydofortheEarth?OceansThelargestecosystemonEarth,covering71%oftheplanet'ssurface.ForestsLargeareasdominatedbytrees,coveringnearlyone-thirdofEarth'sland.WetlandsUniqueecosystemswherewatercoversthesoilforallorpartoftheyear.Task4Readingforthestructure(结构).Anecosystemincludesallthelivingandnon-livingthingsinanarea.

Ecosystemscanbeofdifferentsizes,fromsmallpondstolargegrasslands.

Eachecosystemhasaroletoplayandhelpskeepthebalancebetweenallits

membersandthegreaterenvironment.Theoceanisaverylargeecosystemonearth.Itcoversaround71%oftheearth’ssurfaceandproducesabout70%

oftheearth’soxygen.Itholdsplentyof

saltwater,andthewaterrisestothesky,

fallsontothelandsandthenreturnsto

theocean.Thisgoesonandon,sotheoceanisjustlikethe“heart”ofthe

earth.Wetlandsonlycoverabout6%ofthe

earth’slandarea.Buttheyarehometo

about40%ofallthetypesofplantsand

animals.Plantsinwetlandshelpgetrid

ofpollutionandmakethewaterclean.

Wetlandscanalsohelppreventfloods.

Duringheavyrains,wetlandsstorewaterlikehugesponges.Theyactlikethe“kidneys”oftheearth.Forestsmakeupnearlyathirdofthe

earth’slandarea.Plantstheretakeincarbondioxidefromtheairandproduceoxygen.Theyalsotrapharmfulthingsintheir

leavesandhelpcleantheair.Therefore,peopleoftencallforeststhe“lungs”of

theearth.Eachoftheseecosystemssupportsmillionsofplantsandanimals.Theykeep

theplanethealthyandmakeourworldabetterplace.Whatisan

ecosystem?Whatarethemainecosystems?Howimportantarethe

ecosystems?CarefulreadingC.EcosystemsSustainLifeB.WhatisanEcosystem?A.Forests:Earth’sLungsE.Wetlands:Earth’sKidneysD.TheOcean:Earth’sHeartMatchthemainideaswithparagraphsA.Lookatthepictureandchoosethecorrectdescriptionsforeachecosystemaccordingtothearticle.Writethecorrectlettersintheboxes.a

Cover71%oftheearth’ssurfaceb

Covernearlyathirdoftheearth’s

landareac

Helpcleanthewaterd

Helpmaketheaircleane

Helppreventfloodsf

Produceabout70%oftheearth’soxygeng

The“heart”oftheearthh

The“lungs”oftheearthi

The“kidneys”oftheearthafg-a:“coversaround71%oftheearth’ssurface”P2-f:“producesabout70%oftheearth’soxygen”P2-g:“theoceanisjustlikethe‘heart’oftheearth”P2cei-c:“Plantsinwetlandshelpgetridofpollutionandmakethewaterclean”P3-e:“wetlandscanalsohelppreventfloods”P3-i:“Theyactlikethe'kidneys'oftheearth”P3bdh-b:“Forestsmakeupnearlyathirdoftheearth’slandarea”P4-d:“Plantsthere...helpcleantheair”P4-h:“peopleoftencallforeststhe‘lungs’oftheearth”P4CarefulreadingCarefulreadingAnecosystemincludesallthelivingandnon-livingthingsinanarea.

Ecosystemscanbeofdifferentsizes,fromsmallpondstolargegrasslands.

Eachecosystemhasaroletoplayandhelpskeepthebalancebetweenallits

membersandthegreaterenvironment.1.Whatisanecosystemmadeupof?a

Oceans,wetlandsandforests.b

Plantsandanimals.c

Livingandnon-livingthings.Readpara.1andchooseCarefulreadingReadpara.2andchoose2.Whyistheoceanthelargestecosystemofthethree?a

Itholdsplentyoftheearth’swater.b

Itmakesupabout71%oftheearth’ssurface.c

ItishometomanykindsofplantsandanimalsTheoceanisaverylargeecosystemonearth.Itcoversaround71%oftheearth’ssurfaceandproducesabout70%

oftheearth’soxygen.Itholdsplentyof

saltwater,andthewaterrisestothesky,

fallsontothelandsandthenreturnsto

theocean.Thisgoesonandon,sotheoceanisjustlikethe“heart”ofthe

earth.CarefulreadingReadpara.3andchoose3.Whatdowetlandsdoduringheavyrains?a

Theymakethewaterclean.b

Theyholdwater.c

Theygetridofwater.Wetlandsonlycoverabout6%ofthe

earth’slandarea.Buttheyarehometo

about40%ofallthetypesofplantsand

animals.Plantsinwetlandshelpgetrid

ofpollutionandmakethewaterclean.

Wetlandscanalsohelppreventfloods.

Duringheavyrains,wetlandsstorewaterlikehugesponges.Theyactlikethe“kidneys”oftheearth.Carefulreading4.“Theyalsotrapharmfulthingsintheirleavesandhelpcleantheair.”Whichwordcanweusetoreplacetheword“trap”?a

keep

b

drive

c

produceReadpara.4andchooseForestsmakeupnearlyathirdofthe

earth’slandarea.Plantstheretakeincarbondioxidefromtheairandproduceoxygen.Theyalsotrapharmfulthingsintheir

leavesandhelpcleantheair.Therefore,peopleoftencallforeststhe“lungs”of

theearth.5.Wherecanwereadthiskindofarticle?a

Inanewspaperb

Inatravelguide.c

Inageographymagazine.1.Whyarethe