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

(共26张PPT)
Unit 5
Look into Science
Lesson 26
学习目标
1
2
3
掌握单词： match
接触单词：holder, shallow, lighter, examine, oxygen
短语：use up, be made up of
相信科学，热爱科学，运用科学，服务人类。
掌握本课所学的单词和英语表达；能用英语描述实验步骤及所看到的实验现象。
新课讲授
Free talk
Do you like doing science experiments Why or why not
What experiment have they done before
What will happen if you put a jar upside down over a burning candle
Yes, because experiments can enable us to explore the mysteries of nature.
Air Pressure test.
candle
a candle holder 烛台
/ h ld / n. 支托物；持有者
New words
a shallow plate
/ l / adj. 浅的
lighter
matches
holder n. 支托物；持有者
shallow adj. 浅的
lighter n. 打火机；点火器
match n. 火柴
examine/ ɡ z m n / v. 检查
oxygen / ks d n/ n. 氧气
Read and put the sentence in the right order.
Light the candle.
Examine the water in the jar. What can you see
Carefully put the jar over the candle until the top of the jar rests on the dish .
Put the candle in the candle holder.
Fill the dish half full with water.
Let the candle burn for two or three minutes.
Put the candle holder on the dish.
4
7
6
1
3
5
2
Fast reading
Read and answer the questions.
1. How much water should we fill the dish
2. How long should we let the candle burn
3. Where should we put the jar
4. What is happening
Half full of the dish.
Two or three minutes.
Put it over the candle until the top of the jar rests on the dish.
The water inside the jar rises.
Careful reading
Read and think about.
1. How far does the water rise
2. Why does the water rise
One fifth of the jar.
When the candle stops burning, it has used up all the oxygen in the jar. So the air pressure outside the jar is stronger than that in the jar, and the force of the air outside makes the water inside rise.
Read the lesson and fill in the blanks.
Let's 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 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 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
uses
burning
rises
one fifth
1. a lighter or matches 打火机或火柴
match
① n. 火柴，复数形式为matches。
a box of matches 一盒火柴
② n. 比赛，复数形式matches。
three basketball matches 三场篮球赛
③ v. 相称；相配
Your tie matches your suit. 你的领带和你的套装相配。
Language points
2. Examine the water in the jar. 检查广口瓶里的水。
examine v.
① 检查。 后接名词或代词作宾语。
The doctor examined the patient. 那位医生检查了那位病人。
② 考核，测验
Our teacher will examine us on history.我们老师将测验我们历史。
【拓展】examination（examine的名词形式）检查，考试
All patients had a complete physical examination.
所有的病人都进行了全面体检。
have an entrance examination 参加入学考试
3. When the candle stops burning, it has used up all the oxygen in the air. 当蜡烛停止燃烧时，它用尽了空气中所有氧气。
use up 用光；用尽（=run out of）
其主语往往是人，宾语往往是被用光的物。
Jim used up his money to buy the computer.
吉姆为了买电脑花光了所有的钱。
【注意】use up为“动词+副词”结构，名词作宾语时，位于up前后都可，人称代词作宾语时，须放于use 与up之间。
There is no paper. We have used it up.
没有纸了。我们已经用完了。
类似的还有：think over, look up, put up, eat up, take away, …
4. Because about one fifth of the air is made up of oxygen …
因为空气中氧气的含量大约占五分之一……
（1）分数的表达
分数=
分子
分母
基数词
序数词
>1
序数词+s
1/3 one third 1/6 one sixth
3/4 three fourths 2/5 two fifths
【注意】 “分数+of+名词”作主语时，谓语动词的单复数由of 后名词的形式而定。
About two thirds of the water in the river comes from Yi River.
这条河三分之二的水来自沂河。
About two thirds of the children like playing computer games.
三分之二的孩子喜欢玩电脑游戏。
(2) be made up of … 由……组成
表示由多种成分、团体、成员或单位等组成，并强调整体的构成或组成。
The team is made up of 5 doctors and 10 nurses.
这个队由5名医生和10名护士组成。
【拓展】make up 组成，构成，形成
Women students make up 56% of the student numbers.
女生占学生人数的56%。
5. Read, find and translate.
fill … with sth.
on the dish
put … over sth.
the top of
stop doing sth.
use up
one fifth of …
be made up of …
用某物装满……
在盘子里
把……罩在某物上面
……顶部
停止做某事
用光，用完
……的五分之一
由……组成
Circle the correct words to complete the sentences.
1. Don't (use up /push up) all of the ink. Leave some for me.
2. The medical team (is made of / is made up of) five experienced doctors.
3. Please fill the hole (with /in) sand and water.
4. They didn't realize their mistake (until /as) we told them.
5. My brother wasn't (strong enough/enough strong) to lift the box.
put…in
put…on
fill…with
light
let…burn
carefully put…over
examine
Retell
Read about the experiment in this lesson.
With a group of classmates，practice the experiment.
Do your experiment in front of the class.
Don't 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.
REPORT ON AN ACCIDENT
单项选择。
1. _____ of the students in our class ____ going to summer camp
in Beijing next week.
A. Two fifths; is B. Second fifths; are
C. Second fifths; is D. Two fifths; are
2. If success is a gate, the road towards it must _______difficulties.
A. be made of B. be made from
C. be made up of D. be made by
D
C
当堂检测
3. We have ______ all the water. Please give us some more.
A. turned up B. used up C . eaten up D. set up
4. Please fill the jar ______ oil.
A. of B. with C. into D. over
5. We should stop _______ disposable chopsticks (一次性筷子) and remember to protect the forest.
A. use B. to use C. used D. using
B
B
D
课堂总结
1.本课所学的词汇
match holder shallow
lighter examine oxygen
use up be made up of
2. 如何描述实验步骤