七年级英语上册 CHAPTER FOUR The world of numbers课件 深圳牛津版

Chapter4TheworldofContentsReading

Listening

Language

Speaking

WritingReadingAWhatdoyouknowabout…

Weallusenumbersinourdailylife.Numbersareaninternationallanguage.Whatdoyouknowaboutthelanguageofnumbers?Learnthefollowing:

Adecimalnumberiswrittenasadot.eg.0.65(zeropointsixfive/sixty-five)8.08(eightpointoeight.)Readthefollowing:7.53,3.42,0.01,86.201adecimalnumber(小数）

Oddnumberscannotbedividedbytwotogiveawholenumberwithoutafraction.

2oddnumbers(奇数）3evennumbers(奇数）

Evennumberscanbedividedbytwotogiveawholenumber.

Afractionistheexactdivisionofanumber.eg.½:onehalf2/3:twothirds¼aquarter1/10onetenthReadthefollowing:3/5,6/11,1/8

4afraction(分数）

5plus,add(加）

２＋５＝７Twoplusfiveisseven.Twoandfiveisseven.Twoaddedtofiveisseven.3+12=?Whatis3plustwelve?

Readthefollowing:25+24=4930+12=?

6minus(减，减号，负号）subtract(减)12-3=9Twelveminusthreeisnine.Threesubtractedfromtwelveisnine.

Readthefollowing:2-2=019-12=797-65=?

7times,multiply乘２×３＝６Twotimesthreeissix.Twoandthreemultiplymakessix.Twomultipliedbythreemakes6.

Readthefollowing:16×4=645×3=15

8divide除30÷6=5Thirtydividedbysixisfive.Readthefollowing:20÷4=518÷3=6

45%

=

90oapercentageequalsanumbershowingdegreesMatchthewordswiththepictures,signsandnumbers.1ademicalnumber2apairofoddnumbers3afraction4zero5add;plus6subtract;minus

7multiply,times8divide9anumbershowingdegrees10apercentage11apairofnumbers12equalsAWhatdoyouknowabout…jfcbalidhkge1abacus:

anoldformofcalculator2accurate:withnomistakes3ancient:veryold4atleast:notlessthan5bead:asmallballwithaholethroughthemiddle6calculate:usenumberstofindanswers7consistof:

bemadeupofsomething8develop:growbiggerand/orbetter9electronic:

usingelectronsforpower10electronic:usingelectronsforpower11figure:asymbolratherthanaword12flash:averyshorttime,aninstant13however:yet14international:connectedtomorethanonecountryornation15invent:makeforthefirsttime16nearly:almost17powerful:strong18system:groupofthings/partsthatworktogetherFillintheblankswithcorrectwords.Ifyou_______8and5,youget13.Iusethepocket___________tocheckmyanswers.TheUNisan______________organizationwhichhelpstokeepapeacefulworld.TheundergroundispartofShenzhen’stransport___________.The_________Chinesedrewpicturestoshowdifferentmeanings.addcalculatorinternationalsystemancientFillintheblankswithcorrectwords.6.Beforecalculatorswereinvented,theChinesepeopleused_________tocount.7.Weatherreportsarenotalways__________.Edison_________thelightbulbafterhehadfailedmanytimes.Ifyou_________8from16,youget8.Ourcountryismore__________thanbefore.Ifyou_________28by7,theansweris4.Thecommittee_________oftenmembers.abacusaccurateinventedsubtractpowerfuldivideconsistsC1Findthesewordsinthearticleonpage73.Readthewordsaroundthemandchoosethebestmeanings.1ancient:manymanyyearsago2consistsof:includes3invented:madeforthefirsttime4accurate:withoutmistakes5percentages:amountsoutofahundred

C2FindthewordsinColumnAinthediaryonpage62andmatchthemwiththemeaningsinColumnB.A1international2system3developed4calculate5bottom6powerfulBagrewbiggerorstrongerbagroupofthingsworkingtogetherccountwithnumbersdstrongeusedbymorethanonecountryornationfinthelowestplaceC3Whatdothefollowingdescriptionsreferto?Writedownthecorrectnamesintheblanks.1Acalculatingmachinethatuseswiresandheads.

An___________2Asmallmachinethatdoescalculations.

A___________3Averypowerfulmachinefordoingcalculations.

A__________

abacuscalculatorcomputerCalculatingMachineanabacusCalculatingMachineoneofthefirstcalculatingmachinesaccurate

andfastrepresentbeadswires5,7

2

4—

thousands—

hundreds—

tens—

onesanabacusCalculatingMachineanelectroniccalculatoraddsubtractmultiply

dividepercentagesquarerootcalculateCalculatingMachineanelectroniccalculatorA:Whatcananelectroniccalculatordo?B:Itcan_________,_________,_________and_________.A:Whatelsecanitdo?B:Itcancalculate___________and___________.addsubtractmultiplydividepercentagessquarerootsCalculatingMachineA________isavery_______calculatingmachine.______,itcandoacalculationthatyoucouldnotdo__________________.acomputer

computerpowerfulinaflashinyourwholelifetime

powerful

Inaflash

inyourwholelifetimeNumbers:everyone’slanguageAncientnumbers

Inancienttimes,peoplewrotenumbersinmanydifferentways.However,theynearlyallcountedintens.differentwaysofwritingthenumber6（在古代）（以很多不同的方式）（以十为单位）Numbers:everyone’slanguageZero(0)

Thesystemofnumberstodayconsistsofthenumbersfrom1to9and0(zero).TheIndiansfirstinventedanddevelopedthe1to9systemofnumbers.Theytheninventedthezero.Theinventionofthezerohelpedpeoplewritebignumbersandcalculatemoreeasily.Nowuseeachofthesetennumbersoncetowritethebiggestnumber.Whatisit?（数字体系）（由…组成）（印度人）（发展）（invent.v.inventionn.inventorn.）9876543210Numbers:everyone’slanguageCalculatingmachines(计算工具）oneofthefirstcalculatingmachineswasanabacus.Abacusesarefastandaccurate.Ontheabacus,thebeadsonthewiresstandforones,tens,hundredsandthousands,startingfromthebottomwire.（珠子）（代表standfor）（底部的横杆）Theabacusinthepictureshowsanumber.Writeitdowninfiguresandtheninwords.Multiplyitbyzeroandthenadd1.Whatistheanswer?（用数字）（用文字）Numbers:everyone’slanguage

Modernelectroniccalculatorscanadd,subtract,multiplyanddivide.Itcanalsocalculatepercentagesandsquareroots.（平方根）Numbers:everyone’slanguage

Computersareverypowerfulcalculatingmachines.Acomputercandoacalculation

inaflash,butyoumightnotbeabletodoitinyourwholelifetime.（强大的）（做计算）（一瞬间）（能够做）（一辈子）MayisaskingTMLi,thewriter,somequestionsabouthisarticleonnumbers.Hisanswersarenotalwaysclear.ReadthearticleandmakeLi’sanswersclearer.Writeonewordineachblank.1Everyoneknowsit.Knowswhat?TheLanguageofnumbers.2Longago,peoplewrotetheminmanydifferentways.Wrotewhat?

Numbers.3.Peopleallcountinthisway.Inwhatway?

Intens.4.TheIndiansfirstinventedthatsystemofnumbers.Whichsystemofnumbers?

1to9.5.Theinventionhelpedpeoplewriteinbignumbers.Whatinvention?

Zero.6.Theyarefastandaccurate.What?

Abacuses.7Computersareverypowerfulones.Verypowerfulwhat?Calculatingmachines.Giveanswerstothesequestionsaboutthearticle.1Howdidpeopleinancienttimescountinthesameway?Theynearlyall__________________.2Whatdothebeadsonthewiresofanabacusstandfor?Thebeadsstandfor________________________________________startingfromthebottomwire.3Whatcanamodernelectroniccalculatordo?Itcan______________________________________.countedintensones,tens,hundredsandthousandsadd,subtract,multiplyanddivide.Giveanswerstothesequestionsaboutthearticle.4Whatelsecanamodernelectroniccalculatordo?Icanalso__________________________________________.5Howquicklycanacomputerdoacalculation?Icandoacalculation_____________________.

calculatepercentagesandsquarerootsinaflash以不同的方式数字体系由…组成电子计算器平方根一瞬间以十为单位计算８代表9做运算10在古代1indifferentways2thesystemofnumbers3consistof=bemadeupof4electroniccalculators5squareroots6inaflash7countintens8standfor9doacalculation10inancienttimesSynopsisbyparagraph:P1:Ancientnumbers–Inancienttimes,numberswerewrittenindifferentways,butcountingwasnearlyalwaysintens.Synopsisbyparagraph:P2:Zero-Everyoneusesthenumbersystem1to9plus0.ThesystemwasinventedbytheIndians.Zeromakesiteasiertowritebignumbersandtocalculate.Synopsisbyparagraph:P3-5:Calculatingmachines–Descriptionsofthreecalculatingmachines:theancientabacus,themodernelectroniccalculatorandthecomputer.

ListeningNowtryaquizaboutnumbers.Listentotheinstructionsontherecording,andcircletherightanswer.

8049172.6626%2/6$7575%75o1/80.753356656690o

90%1/9725653881256628812565288181.8%80%18%9$5,000$50,000$50,000,0001030.5o

13.5o

35o

1Whichoneoftheseisanevennumber?2Whichoneoftheseisafraction?3Whichoneoftheseisapercentage?4Whichoneoftheseisadecimalnumber?5Whichoneoftheseisanoddnumber?6Whichoneoftheseisanumbershowingdegrees?7Myphonenumberis25652881.818percentofmyclassmatescometoschoolonfoot.9Thisringcostsfiftythousanddollars.10Thehighesttemperaturetodaywas30point5degrees.LanguageAImperativesentencesWhenwegiveordersorinstructionstopeople,wetellthemtodoornottodosomething.Weusuallystartthesentenceswithaverb.Weoftenmakeinstructionsmorepolitebystartingwithplease.Sometimeswestartwiththenameofthepersonreceivingtheinstruction.ReadtheinstructionsbelowBequiet.Pleasehaveaseat.David,payattention.Don’tbeafraid.Pleasedonotmakeanoise.Alan,don’tbelate.Readthedialoguesandcompletethemwithimperativesandthecorrectformoftheverbsinbrackets.1It’sherbirthdaynextweek.Then______________heraboutthesurpriseparty.2HowcanIgettoPeople’sHospital?______alongthestreetand________leftatthelights.3Wehavetofinishtheworkintwohours.Thenlet’s__________anytime.4_____________somuchnoise,please.OK.5__________out!There’sacarcoming.Thanks.don’ttellGoturnnotwasteDon’tmakeLookAdd3and9.Subtract3from9.Multiply3by9.Divide9by3.BInstructionsandstatementsaboutnumbersTableI3plus9equals/is12.9minus3equals/is6.3multipliedby9equals/is27.9dividedby3equals/is3.BInstructionsandstatementsaboutnumbersTableIIWorkinpairstoworkouttheproblems.S1tellsS2todothefollowingsums.S2listensandreplies.Thencheckyouranswerstogether.1Add11

and1.2Subtract

5from13.3Multiply7by8.4Divide16by4.5Add9and6.6Add14and4anddividetheanswerby2.7Subtract9from19andmultiplytheanswerby3.S111plus1equals12.13minus5equals8.7multipliedby8equals56.16dividedby4equals4.9plus6equals15.14plus4dividedby2equals9.19minus9multipliedby3equals30.S21Thinkofanumber,butdon’ttellmewhatitis.2Add1.3Multiplytheanswerby2.4Nowadd3.5Nowmultiplyby2again.6Nowsubtract10.7Nowtellmetheanswer.CcardinalandordinalnumbersSaythesecardinalnumbers.313303251550546166067919909821002002103751,0004,18915,362100,000

Ccardinalandordinalnumbers3284,653twohundredandeighty-fourthousandsixhundredandfifty-three

1,000,000onemillion1,367,982onemillionthreehundredandsixty-seventhousandninehundredandeighty-two

CcardinalandordinalnumbersSaythesesentenceswithordinalnumbers.PositioninclassMay:1Mayisfirst.

Alan:2Danny:3June:4Peter:12Alice:19Steve:28CcardinalandordinalnumbersSaythesedecimals..3:pointthree0.3zeropointthree.368pointthreesixeight7.145sevenpointonefourfive36.36thirty-sixpointthreesixSpeakingATalktimeA1Readthesetelephonenumbers.2921514325651351247101222389416720105100272455662978112123564399

WhenwesaytelephoneorIDcardnumbers,wesayeachnumberseparately.For0wesayzerooroh.