八年级英语A-dangerous-servant课件.ppt

八年级英语A-dangerous-servant课件.ppt

《八年级英语A-dangerous-servant课件.ppt》由会员分享，可在线阅读，更多相关《八年级英语A-dangerous-servant课件.ppt（28页珍藏版）》请在冰豆网上搜索。

8BChapter4Adangerousservant8BChapter31.Whatdoyouthinkofelectricity?

Why?

2.Electricitygivespowerforallkindsofelectricalappliances.Canyounamesomeoftheelectricalappliancesweuseinourlives?

（Whenwepluganapplianceintothewallsocket,weareusingelectricityproducedbyagenerator.）electricalappliancesanairconditionerablenderaCDplayeracomputeracookerahairdryeralampakettleelectricalappliancesaheaterafananironamicrowaveanovenaprinterelectricalappliancesarecorderarefrigeratoraTVsetavacuumcleaneravideoplayerawashingmachineamobilephone（afridge）arobotWheredoesarobotsenergycomefrom?

Itsenergycomesfromelectricity.vWheredoesourenergycomefrom?

（Energyisthepowerthatmakesthingswork.）Perhapswithoutelectricityourliveswillnotbeinteresting.Nowletustalkaboutelectricity.Whatisit?

Electricityisthepowerwhichisproducedbyrubbing（friction）,byamachinecalledageneratororbychemicalmeans（e.g.abattery）.Canweseeit?

No,itsakindofenergythatwecannotsee.Itsinvisible.Canwetouchit?

No,wecant.Wemaygetanelectricshock.Itsdangerous.PowerstationspylonshomeDoyouknowhowelectricitycomestous?

Doyouknowhowelectricitycomestous?

Thepylonscarrywires.Wirescarryelectricity.Electricitycomesintoourflatsthroughthinwires,andthethinwiresareconnectedtothickwires.Thethickwiresarecalledcablesandtheyareburiedunderground.Cablesareconnectedtopowerstations.Powerstationsmakeelectricity.Homework:

1.Gooverthevocabularyitemsandrecitethem.2.Listentotherecordingofthearticleandreaditaloudseveraltimes.3.FinishEx.C/D/Eonpage46,47.8BChapter4Adangerousservant8BChapter3Ex.Fillintheblankswithproperwords:

wireenergycableshock1.Youngpeoplehavemorethanoldpeople.2.Donttouchthe!

Youllgetanelectric.3.Whentheworkersweredigginguptheroad,theycutthe,andasaresult,therewasablackoutinthearea.athreadofmetalthepowerthatmakesthingsworkathick,strongropemadeofwireaverystrongforceorblowaperiodofdarknesscausedbyacutintheelectricitysupplyWecanchangeelectricityintoenergythatwecansee,hear,orfeel.Wecanalsochangeitintoenergythatmovethings.lightenergysoundenergyheatenergymovementenergy（movement-movingorbeingmoved）Canyoutellwhatkind（s）ofenergydotheyproduce?

Vocabularyelectricityn.electrica.电的，电动的，发电的电的，电动的，发电的electriccables电缆电缆anelectrickettle电壶电壶electriccurrent电流电流electricala.电的，电气科学的电的，电气科学的electricalappliances电器电器anelectricalengineer电气工程师电气工程师electriciann.电工，电工，电学家电学家Ifanyoftheelectricalappliancesorthewiringinyourhomeisoutoforder,youneedtofindanelectriciantorepairthem.1）Whendidthestoryhappen?

2）BennydidntwanttotrickDaisy,didhe?

3）DoesBennyknowwhatelectricityis?

4）Whymustwebecarefulwithelectricity?

5）Howdoeselectricitycomeintoourhomes?

6）Whatarethewiresconnectedto?

7）WhatdidDaisybuyforherbrother?

8）DoesDaisyknowwhatelectricityis?

9）Howdobatterieswork?

10）WhatdoyouthinkofBennyandDaisy?

Readaloudthearticleandanswerthefollowingquestions:

I.Completethesentences:

1）Itstotouchtheelectricitywithyourhand.（danger）2）Wecanbuysugarin.（pack）3）Hehadnoforwhyhewaslate.（explain）4）Water.hasthree-solid,liquidandgas.（form）5）Thethiefthetreasureunderthetree.（bury）6）Intheolddays,therichusuallyaskedtodothehouseworkforthem.（serve）7）Timworksasanewspaperboyandhegetshispayfromhisboss.（month）Homework:

II.Readandreciteparagraphs413.III.Readandrecitethewordsandexpressions.8BChapter4Adangerousservant8BChapter3Publictransporttrainbusundergroundplanemaglevtrainphrases热能热能/电能电能/声能声能动能动能/原子能原子能精力充沛的精力充沛的不同形式的能量不同形式的能量一包信件一包信件一盒一盒20支香烟支香烟终于终于起先起先埋电缆埋电缆在某种程度上在某种程度上谨慎，小心谨慎，小心变成变成欺骗，欺骗，heatenergy/lightenergy/soundenergymovementenergy/atomicenergybeenergetic/befullofenergydifferentformsofenergyapacketoflettersapacketof20cigarettesatlast/intheend/finallyatfirst/atthebeginningofburycablesinawaybecarefulwith/ofchangeinto/turnintotricksomebody/playatrick（joke）onsomebodyFillintheblanks:

foolbatteryhappinessdangerpoliterealproduce1.Thetreescanprotectthemselvesbyachemicalthatmakestheirleavestastenasty.2.Imsorryaboutmybeinglate,sir.3.Whatis,waterorfire?

4.Wouldyouliketogetmesome?

5.Dontalwaysdosuchthings.6.Heansweredthatquestionyesterday.7.Althoughtheyarepoor,theyare.jointogetherintheendthatcannotbeseenwordsthatmakesth.clearorsaywhatsth.meansshapesorkindspowerthatmakesthingsworkormakespeopledothingsputsomethingorsomeoneinthegroundaverywidesmilethickropesofwirewhichelectricitypassesthroughpowerthat（comesthroughwiresand）canmakeheat,soundandlight,andmovethingsamachinethattellsyoutheamountused（doneorhappening）everymonth