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Lesson30KeeptheCandleBurning!Leadin1.Doyouthinkscienceisinteresting?Whyorwhynot?2.NameoneortwofamousChinesescientists.Whatdoyouknowaboutthem?1.candleholdern.蜡台;烛台2.shallowadj.浅的3.matchn.火柴；比赛4.burn(burned,burnt)v.燃烧5.light(lit,lighted)v.点燃,使燃烧6.oxygenn.氧气7.gray（=grey）adj.灰色的8.one-fifth五分之一PresentationNewwordsTomakeacandleburn,you“light”it.Whatdoyouuse?Amatch.Canyouseethecandleholderinthispicture?Thecandleispink.Thecandleholderisgray.Thecandleholderis“holding”thecandle!Whatdoyouneedtodotheexperiment?Readcarefullyandanswerthequestions.acandleacandleholderabigglassjarashallowdishwithwatermatchesWhatishappening?Whenwelightthecandle,thecandlewill_____.It_________oxygenintheair.Whenthecandlestops_______,therewillbeno______intheair.Thewaterinsidethejarthen_____andfillsabout________ofthejarbecausethereisaboutone-fifthoxygeninthe_____.burnusesburningoxygenrisesone-fifthairupLanguagePoints1.Keepthecandleburning.让蜡烛燃烧着。keep常构成以下词组或句式：keepsth.+adj.例如：Keeptheroomclean.保持房间干净。keepsb.(sth.)+doing/地点使某人(某物)保持某种状态或一直做某事/在哪里Hekeptmewaitingforalongtime.他使得我（让我）等了很久。2.Fillthedishhalffullofwater.把盘子装一半水。half是副词，“部分地，一半地”。例如：halfcookedmeat半熟的肉Thebottleisonlyhalffull.这瓶子只装了一半。half还可以作形容词或名词，“半个的，一半”。例如：halfayear半年halfanhour半小时Halfofthemarehere.他们中的一半到这了。3.Thereisaboutone-fifthoxygenintheair,sothewaterrisesandfillsaboutone-fifthofthejar.空气中大约有五分之一的氧气，所以水会上升至瓶子五分之一的位置。分数的表达：分子用基数词表示，分母用序数词表示。当分子大于1时，要在分母的序数词后加“s”，可记为：分子基，分母序，分子＞1，分母加“s”。例如：1/3onethird(one-third)3/4threefourths(threequarters)(three-quarters)3/5threefifths(three-fifths)Summary1.单词短语：___________(在小组内口头汇报)2.掌握keep，half的用法及分数的表达法。用所给单词的正确形式填空1.Youareverytired.You’dbetterstop_______(have)arest.2.Whatdoyouusetomakeacandle_______(burn)?3.Pleaseputthejaroverthecandle________(careful).4.What______________(observe)canyoumake?5.Pleasecuttheappleinto_________(half).6.He___________(light)acandleandtheroomwasbright.7._______(two),askthestudentstoguesswhatwillhappen.8.Hekeptthecandle__________(burn)fortwohours.tohaveburncarefullyobservation(s)halveslighted/litSecondburningPractice写作：利用业余时间做一下这个实验，把你的实验过程描述出来，看看和书上有什么不同，70词左右。HomeworkThereisnoroyalroadtolearning.书山有路勤为径，学海无涯苦作舟。