八年级英语look into science课件3

,Lesson 30 Keep the Candle Burning!,. Learning aims:, 知识目标Master the new words: match, light, burn, use up, shallow, candleholder, oxygen,one-fifth2) The important sentences: Fill the dish half full of water. As the candle burns, it uses up oxygen in the air. There is about one-fifth oxygen in the air, so the water rises and fills about one-fifth of the jar.,. 教学重点：1. Describe and explain the experiment inEnglish. 2.分数的表达法 .教学难点:Describe and explain the experiment in English.,能力目标 ：can describe and explain the experiment in English情感目标：Cultivate the spirit of loving science.,预习早知道1.match (pl)-_light (过去式）_(过去分词）_burn（过去式）_ (过去分词）_ v. 燃烧use upone-fifthshallow(反义词）_half(pl)_,matches,n. 火柴;比赛,lighted/lit,lighted/lit,v. 点燃;使燃烧/照亮;使光明,burned/t,用完；用光；,五分之一,burned/t,deep,halves,Look and Learn,1 .What are they ?They are_ They are used to _something. I will use them _a candle. I am _ the candle with the match. My father often uses matches _his smoke. 2.This afternoon well have a basketball_.,matches,light,to light,lighting,to light,match,Look and Learn,-Because burning needs _. when the candle stops buirning, it has _ _ all the oxygen in the jar. (_:They have _ all the water. ),Whats this? Its a_ .Its a _candle . If I put the jar over the burning candle, what will happen?,-It will go out / stop _ why?,candle,burning,burning,oxygen,used,up,use up,used up,一. 自主探究，合作学习,1.He _the spoon_the bowl.他把汤匙放到了碗里面。2.Lily _the bottle_water. Lily 把瓶子装满了水。3.The room _ smoking. 屋子里充满了烟。4.Please put the jar _the candle.请把罐子放到蜡烛的 上面。5.My mother_her money to buy clothing yesterday.我妈妈昨天买衣服花光(用光）了她身上所有的钱。6.In our class,_ students are boys,_ students are girls. 在我们班，三分之二的学生是男生，三分之一的学生是女生。二. 小组合作操练，用上述新知识点造句，并在小组 内核对，交流。,put,in,filled,with,is full of/is filled with,over,used up,two-thirds,one-third,点拨 Comepare and Find,One - fifth four fifthsone - third two - thirds,分数表达法分子基分母序分子大于 1分母加 S,1/5 4/5 1/3 2/3,基数词,序数词,分子,分母,5/9,Practise,1/4,one-fourth,3/7,three-sevenths,. There is about one-fifth oxygen in the air, so the water rises and fillsabout one-fifth of the jar.,a quarter,five-ninths,强化训练,单项选择1.The bottle is only_full. A.half B.a half C. halfs D.halves2.She _the chicken bones to make soup.A.Used for B. used to C.used up D.used with3._of the students in our school_from countryside.(乡村）A.Four-fifths,comes B.Fourth-five,come C.Four-fifth,come D.Four-fifths,come4._of water_. A. Three-fourths, are B.Three-four，is C.Three-quarters，is D. Three-fourth, is4.The river is _here; we can walk across. A. deep B. fast C. shallow5.Yellow is a _colour, but black is dark. A. orange B. light C. heavy,A,C,D,C,C,B,Watch ,Say,answer and Fill,First. _the candle _the candleholder.Then. _the candleholder _the dish.Third. _the dish _water .Fourth. _the candle .Fifth. _the candle _for two minutes .Sixth.carefully_the jar_the candle until the top of the jar_on the dish. What observation can you make?,How do we do the experiment,put,put,in,in,Fill,half full of,Light,let,burn,put,over,rests,Think ,Read and Anwser,1. Why did the candle stop burning ?because there was _oxygen in the jar .2. Why did the water rise ?The force outside the jar is _ than the force inside the jar .,3. How far did the water rise ? Why? It rose about _of the jar .Because there is one-fifth oxygen in the_.,no,stronger,one-fifth,air,summary,The new words: match, light, burn, shallow, candleholder, oxygen, The phrases and expressions: use up, one-fifth, keep sb/sth doing, keep sth/sb +adjStop doing/to do sth, put.in/over分数的表达：分子基，分母序，分子大于 1，分母加 S sentences Fill the dish half full of water. As the candle burns, it uses up oxygen in the air. There is about one-fifth oxygen in the air, so the water rises and fills about one-fifth of the jar.How do “ keep the candle burning”,用所给单词的正确形式填空：1.You are very tired. Youd better stop _(have) a rest.2. What do you use to make a candle _(burn)?3. You should put the jar over the candle _(careful).4. What _(observe) can you make?5. Please cut the apple into _(half).6. He _(light) a candle and the room was bright.7. He kept the candle _(burn) for two hours.8. Its time _(play) basketball.9. Eating green food can help to keep you _ （health）.10.Im sorry, I kept you_ (wait) for a long time.,to have,burn,carefully,observatio