Unit4Period2课时课件牛津上海版英语八年级上册

Watchthevideoclip.3-3Saythefollowingdecimals.123twenty-sixpointtwothreeforty-eightpointfoureightfivehundredandtwenty-sixpointfourthreetwoonepointofoursixeightFractions4-1123Herearetwofractions.Howcanwereadthem?UsecardinalnumbersUseordinalnumbersonethird44-2Notethesespecialfractions:123a/onehalfa/onequarter44-3123Howtosayamixedfraction?44-41234Saythefollowingfractions.one-eighthfourteentwenty-secondstwenty-twoandeleven-nineteenthsExercisesInpairs,practisesayingthefollowingnumbers.0.719.211/553.358¾7/90.1686½zeropointsevennineteenpointtwooneone-fifthfifty-threepointthreefiveConsolidationWorkbook8A,page33.Answer

the

questions.3.Whatdoesanelectroniccalculatorallowustodo?TheIndians.1.Whoinventedanddevelopedthenumberzero?2.

Whatisthemostbasicnon-electroniccalculator?Anabacus.4.Whatistheadvantageofacomputer?Itcansolvedifficultproblemsinaflash.Itallowsustoadd,subtract,multiply,divide,findpercentagesandsquareroots.doallkindsofcalculations.Thinkandanswerthequestions.Whattypeoftextisthis?Itis

aninformationaltext/exposition(说明文).Whatisthemainpurposeofthetext?Wherecanyouprobablyfindthisarticle?a) Toinform（告知）b) Toentertain（娱乐）c) Topersuade（劝说）a)Inahistorytextbookb)inanovel(小说)√作者的写作目的√10Whathelpsyoudivideitinto4parts?Subheadings(小标题).Subheadingsplayanimportantroleinholdingthereaders’attention.Whatmakesgoodsubheadings?directandtothepoint紧扣主题interestingconsistent保持一致性a)lengthb)structureshortandclearReadthesubheadingsofthetext.AncientnumbersZeroCalculatingmachinesBrainagainstcomputerAretheyshortandclear?√Aretheyofsimilarlength?√Aretheyconsistent(一致的)instructure?√AtopicsentenceAtopicsentenceisthemostimportantsentenceinaparagraph.Itsummarizes(总结)theinformationintheparagraph.Inmostcases,atopicsentenceappearsatornearthebeginningortheendofaparagraph.主题句/中心句Read“Ancientnumbers”.Underlinethetopicsentence.factsandreasons15Read“Calculatingmachines”.Findthetopicsentence.

Canyouwriteatopicsentence?Calculatingmachinesareourgoodhelperstododifficultcalculations.examplesanddescriptionsRead“Brainagainstcomputer”.Underlinethetopicsentence.Howdoesthewriteranswerthisquestion?Bygivingexamplesandmakingcomparisonandcontrast(作比较).Thinkandanswerthequestion.1.Supposethecompetitiontookplaceatpresent,woulditbepossibleforamathsgeniuslikeShakuntalatobeatacomputer?Atthattime,itwaspossibleforamathsgeniustobeatacomputer.Today,itwouldprobablybeimpossibleastechnologyhascomeaverylongway.Acomputerrunsmuchfasterthanahumanbrain.2.Doyouthinkcomputerswillbesmarterthanhumansinthefuture?Whyorwhynot?Idon’tthinkcomputerswillbesmarterthanhumansinthefuture.Becauseourbrainscanunderstandthemeaningofthingsbetterandcreatenewideas.Computershavetobeprogrammedwithinstructionsbyhumans.Theythemselvescannotcreatenewideas.SupportingdetailsSubheadingsTopicsentencesSubheadingsdividethetextintosectionsandtellthetopicofeachsection.shortclearconcise简练

Topicsentencesexpresswhattheparagraphisabout.topiccentralpointSupportingdetailsincludefacts,examples,anecdotes,reasonsordescriptivedetails.DecimalsHerea