1、,Unit 5 Look into Science,Lesson 26 Keep the Candle Burning,Think about it! Do you think science is interesting? Why or why not?2. Name one or two famous Chinese scientists. What do you know about them?,Lets do another experiment.,Keep the Candle Burning.,What do we need?,a candle,蜡烛,a big glass jar
2、,玻璃罐子,a candleholder,烛台,a shallow dish with water,浅的,matches,火柴,a match,一根火柴,How do we do the experiment? Lets read the text and fill in the blanks.,Lets do the experiment together! Put the candle in the candle holder. Put the candle holder on the dish. Fill the dish half full with water. Light the
3、candle with a or a lighter. What can you see? The candle is burning. _ the candle burn for two or three minutes. Then carefully put the jar _over it until the top of the jar rests on the dish. As the candle burns, it the oxygen in the air. When the candle stops , it has used up all the oxygen in the
4、 air. The water inside the jar and fills about of the jar. This is because about one fifth of the air is made up of oxygen.,match,Let,burning,rises,What is happening?,1) 分数由分子和分母两部分构成。用英语表达时，分子用基数词，分母用序数词。 2) 如果分子为1，则分母的序数词是单数形式，如果分子大于1，则分母的序数词用复数形式。 one (a) half 或 one second (one-second) = one (a)q
5、uarter 或 one-quarter,How to express the fractions:,口 诀: 分子基，分母序。分子1 ，分母加s 。,二分之一 三分之一 四分之一 四分之三 五分之二 十分之九,a/one half (one second) one-third one quarter three-fourths three quarters two-fifths nine-tenths,1. Practice the text in groups.2. Finish the exercise on page 69.,Do the experiment what you wan
6、t in groups. Read about the experiment in this lesson.With a group of classmates,practice the experiment.Do your experiment in front of the class.Dont forget the following things: First,describe your experiment. Second,ask the class what they think will happen. Third,do the experiment. Finally,ask the class if the result is what they expected.,Write the progress in the experiment.,1.Listen and read. 2.Finish exercises of this lesson.,Homework,
