Unit6Whenwasitinvented第四课时SectionB(1a～1e)【学习目标】1．能够通过听说学习与食物有关的词汇。2．让学生通过阅读理解如何用一般过去时的被动语态描述发明史。【学习重点】重点单词及短语：sour，bymistake【学习难点】学会用一般过去时的被动语态对更广泛的发明进行描述。☞学习提示Teacherhelpsstudentstoreviewthewordsaboutfoodbyasking：Howdoes…taste？Encouragestudentstorecallmoreadjectivestodescribethesefruitsandfood.Task1☞学习提示PreviewthewordsonP45，readthewordsbyphoneticsymbolsandmarkthenewwordsinthetext.Finallyfinishthetaskof1a.Task2☞学习提示ListentothetapeonP45andfinishthelisteningtasksin1c.Thenstudentslistentothetapeagainandfinishthelisteningtaskin1d.Listentothetapeforthirdtime，finishthecomplementarytasks.(A)1.Whenwerepotatochipsinvented?A．In1853.B．In1850.C．In1835.(B)2.Whoinventedthepotatochips?A．Acustomer.B．Acook.C．Aboss.(C)3.Whywastheplateoffriedchipssentback?A．Becausetheywerecrispy.B．Becausetheywerecutthin.C．Becausetheywerecuttoothick.情景导入生成问题T：Doyouknowhowtheapplescantaste?S1：Yes.Theymaytastesweet.T：Andtheoranges?S2：…sweetbananas；crispypotato__chips；saltynoodles；sourgrapes.自学互研生成能力Task1Let'sreadnewwordsandthephrases.1．Icanread.(我会读)预习下列单词，争取自己能正确拼读。拼读成功后再在课文中把单词标记出来。crispy，salty，sour，bymistake，customer2．Icanwrite.(我会写)翻译下列短语：(1)morethanone不止一个(2)thinenough足够薄(3)intheend最后Task2Let'slistentothetapeandfinish1c，1d.Task3Let'smakeconversationsandinterview.1．Icantranslate.(我会译)(1)你知道土豆片是在无意中发明的吗？Didyouknowpotatochipswere__invented__by__mistake?(2)顾客认为土豆不够薄。Thecustomerthoughtthepotatoeswerenotthin__enough.(3)最后他在它们上面撒了许多盐以使它们足够咸。Finallyheputlotsofsaltonthemsotheyweresaltyenough.2．Icanmakeconversations.(我会编对话)你能结合课文内容编写对话，讨论薯片的发明过程吗？A：Did__you__know__potato__chips__were__invented__by__mistake?B：Wow，I__didn't__know__that.Who__invented__them?A：They__were__invented__by__a__chef__called__George__Crum.B：When__were__they__invented?A：They__were__invented__in__1853.B：How__were__they__invented?A：George__Crum__cooked__them__for__a__long__time__until__they__were__crispy.And__he__put__lots__of__salt__on__them__so__they__were__really__salty.(A)4.Whatdidpeoplethinkofthethinlysliced，saltychips?A．Theylikedthemverymuch.B．Theynolongeratethem.C．Theyhatedthem.(C)5.Whatisthepassagetalkingabout?A．Acaraccident.B．Thewayofcookingpotatochips.C．Theinventionofpotatochips.【学法指导】►mistake①mistake作名词，意为“错误”。bymistake是介词短语，意为“错误地”；makeamistake意为“犯错误”。②mistake作动词，意为“弄错，误解”。mistake…for…意为“把……误当作……”。►enoughenough作形容词时，enough＋n.＝n.＋enough；enough作副词时，adj./adv.＋enough＋todo…意为“够……而能做……”。Task3☞学习提示【备注】结合1c和1d完成教材1e的任务，要求学生模仿听力内容，进行对话练习，谈论物品的发明者，发明时间等。Accordingto1Cand1dcompletetextbook1etask，requirestudentstoimitatethelistening，carryontheconversationpractice，talkabouttheinventedoftheobjectsinventedtimeandsoon.3.Icansummarize.(我会总结)归纳until的用法：(1)until用于肯定句中，意为“(一直到)……为止”，主句中的谓语动词必须是延续性动词，表示这一动作或状态延续到until状语所表示的时间为止。(2)until用于否定句中，即not…until，意为“直到……才”。它表示主句的动作直到until状语所表示的...
