Unit 5 Look into Science Lesson 26 Keep the Candle Burning 教学课件 （34张PPT）

课件34张PPT。 Lesson 26
Keep the Candle Burningcandle
Candleholder
jara matchmatcheslight(点燃，使燃烧）lightedlightedlitlitburn燃烧burnedburnedburntburnt use up 用光，用完 Shallow浅的lowcandle蜡烛点燃烧，使燃烧烛台浅的燃烧candleholdershallowlightburn用光氧气oxygenuse upWhat do you need?1.a candle2.a candleholder3.a big glass jar4.a shallow dish 5.some water 6.matchesWhat do we do?1、put the candle in the candle holder 2.put the candleholder in the dish3.fill the dish half full with water 4..light the candle. 5.Let the candle burn for two or three minutes. 6.Carefully put the jar over the candle until the top of the jar rests on the dish. 7.Examine the water in the jar. 1、put the _________in
the ___________ 2、put the _____________ in the _____ 3、Fill _____ half full with____　______ 4、______the candle 5、let the candle ____ for two or three minutes candle candleholder candleholder dish dish water Light burn 6、Carefully put the ______ over the ________ until the top of the jar rest on the dish. 7、Examine the _____ in the jar. jar dish water Practise the experiment in groups. Remember to tell you classmates what to be need ,what to do and what will happenWhat can you see?What is happening?Guess what will happen :1. Candles keep burning.( )2.Candles stop burning. ( )5.The water inside the jar will rise. ( )3 .The water inside the jar will be still. ( )4.The water inside the jar will go down. ( )NOYesNONOYesⅠ.How far does the water rise and fill the jar? Ⅱ.Why?The water rises and fill about one-fifth of the jar.Because there is about one-fifth oxygen in the air .The candle uses up all the oxygen in the jar.1、As the candle burns ,it uses up oxygen in the jar .2、When the candle stop burning ,it has used up all the oxygen in the jar .3、The water inside the jar then rises .4、there is about one-fifth oxygen in the air ,so the water rises and fills about one-fifth of the jar.1. The water here is s______, not deep.
2. Let the fire b______ for a few hours. The room will be very warm.
3. Look! The boy is playing with some ________ (火柴).
4. There is little ______ (氧气) at the top of the mountains.
5. Mr. Black sat down and __________ (点燃) a candle.I. 根据首字母或汉语提示，完成下列句子。lighted hallow urnmatchesoxygenLanguage points one-fifthone-thirdtwo-thirds three-fourthsfive-sixthsfive-tenths分子基数词，分母序数词五分之一 分子大于1，分母加S1. When the candle stops burning, it has used up all the oxygen in the air.
当蜡烛停止燃烧时，它已经耗光了空气中的氧气。use up 用尽；耗光He has used up all his energy.
他已筋疲力尽。
By this time he had used up all his savings.
到这时, 他的存款已全部用完。 2. Because about one fifth of the air is made up of oxygen, the water rises and fills about one fifth of the jar.
因为空气的五分之一是由氧气组成的，所以水会上升到瓶子五分之一的位置。be made up of “用……构成或组成的”，指结构成分，指人、物皆可。I want my staff to be made up of excellent workers.
我希望我的员工都非常出色。1. Please pass me the bottle full ______ water.
2. He is so hungry that he has eaten ______ all the food on the plate.
3. I usually put the candle ______ the candle holder.
4. Mr. Gao came into the classroom ______ a book in his hand.
5. The rainy day will last ______ three days. II. 用适当的介词填空。forwithupinwith1. 当蜡烛停止燃烧时，它已用光了空气中所有的氧气。
When the candle _______ ________, it ____ ______ ______ all the oxygen in the air.
2. 我们班里五分之三是女生。
__________ of the students in our class are girls.
3. 为了完成那项工作，他工作了十个小时。
____ _____ the work, he has worked ____ ten hours.III. 根据汉语提示，翻译下列句子。stops burning hasused upThree fifthsTo finish forThank you very much