八年级英语下册 Unit 4 Look into Science Lesson 30 Keep the Candle B

Lesson 30Keep the Candle Burning!

Ⅰ. Learning aims:知识目标 Master the new words: match, light, burn, use up, shallow, candleholder, oxygen,one-fifth 2) The important sentences: ① Fill the dish half full of water. ② As the candle burns, it uses up oxygen in the air. ③ There is about one-fifth oxygen in the air, so the water rises and fills about one-fifth of the jar. ◆能力目标 ：can describe and explain the experiment in English ◆情感目标：Cultivate the spirit of loving science.◆

教学重点： Ⅱ. 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. Ⅲ.教学难点 教学难点

预习早知道1.match (pl)----__________ 火柴;比赛 light (过去式)___________(过去分词)____________________ 过去式) 过去分词) n. 火柴 比赛 过去式 过去分词 matches burn(过去式)___________ (过去分词)________ v. 燃烧 过去分词) (过去式) 过去分词 lighted/lit lighted/lit use up one--fifth 使燃烧/照亮 使光明 v. 点燃;使燃烧 照亮;使光明 点燃 使燃烧 照亮 shallow(反义词)________ 反义词) 反义词 burned/t half(pl)______

burned/t 用完；用光； 五分之一halves

deep

Look and Learnmatches 1 .What are they ?They are________ light They are used to _______something. I to light will use them ________a candle. I am _______ the candle with the lighting match. My father often uses matches to light _______his smoke. 2.This afternoon we’ll have a match basketball_______.

Look and Learn

What’s this? It’s a______ .It’s a candle burning _______candle . If I put the jar over the burning candle, what will happen?burning ----It will go out / stop _______ why? oxygen -----Because burning needs _______. when the candle stops buirning, it has ___ up used ____ all the oxygen in the jar. use up (______:They have used up all the _______ water. )

自主探究， 一. 自主探究，合作学习put in 1.He _____the spoon____the bowl.他把汤匙放到了碗里面。 with filled 2.Lily _____the bottle____water. Lily 把瓶子装满了水。3.The room is full of/is filled with smoking. 屋子里充满了烟。 ___________________

over 4.Please put the jar _____the candle.请把罐子放到蜡烛的 上面。 used up 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。

two-thirds one-third 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。小组合作操练，用上述新知识点造句， 内核对， 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。

点拨

Comepare and Find

. There is about one-fifth oxygen in the air, so the water rises and fillsabout one-fifth of the jar.分数表达法分子基

分子 分母基数词 序

数词

Practise 1/4 one-fourth a quarter 3/7 three-sevenths5/9

分母序

1/5 4/5 1/3 2/3

One - fifth four – fifths one - third two - thirds分子大于 1 分母加 S

five-ninths

强化训练单项选择

A 1.The bottle is only____full. A.half B.a half2.She ____the chicken bones to make soup. C http://www.77cn.com.cned for B. used to http://www.77cn.com.cned up

C. halfs D.halves

http://www.77cn.com.cned with

3.___of the students in our school____from countryside.(乡村) D A.Four-fifths,comes B.Fourth-five,come C.Four-fifth,come D.Four-fifths,come

C 4.____of water____. A. Three-fourths, are B.Three-four,is C.Three-quarters,is D. Three-fourth, is C 4.The river is _____here; we can walk across. A. deep B. fast C. shallow B 5.Yellow is a _______colour, but black is dark. A. orange B. light C. heavy

Watch ,Say,answer and Fill

How do we do the experimentFirst. _____the candle ____the candleholder. put in Then. _____the candleholder ____the dish. put Third. _____the dish ___________water . in Fourth. ______the candle . Fill half full of Fifth. ______the candle ______for two minutes . Light Sixth.carefully____the jar_____the candle burn dish. let until the top of the jar_____on the

What observation can you make? put over

rests

Think ,Read and Anwser

1. Why did the candle stop burning ? no 2. Why did the water rise ?

because there was ___oxygen in the jar . The force outside the jar is ______ than the force inside the stronger jar .

3. How far did the water rise ? Why?one-fifth It rose about ____________of the jar . air Because there is one-fifth oxygen in the_____.

summaryThe new words: match, light, burn, shallow, candleholder, oxygen, The phrases and expressions: use up, one-fifth, keep sb/sth doing, keep sth/sb +adj Stop 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 分子基， 1, 分子基 分母序， sentences ① Fill the dish half full of water. ② As the candle burns, it uses up oxygen in the air. ③ 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： 用所给单词的正确形式填空：to have 1.You are very tired. You’d better stop ______(have) a rest. burn 2. What do you use to make a candle ________(burn)? carefully 3. You should put the jar over the candle ________(careful). observation(s) 4. What ______________(observe) can you make? halves 5. Please cut the apple into __________(half). lighted/lit 6. He __________(light) a candle and the room was bright. burning 7. He kept the candle _________(burn) for two hours. to play 8. It’s time ___________(play) basketball. healthy 9. Eating green food can help to keep you __ ______ (health). ) waiting 10.I’m sorry, I kept you______ (wait) for a lon …… 此处隐藏：3130字，全部文档内容请下载后查看。喜欢就下载吧 ……