课件51张PPT。Unit4 Global warmingQMQ.The Earth Is Becoming Warmer – But Does It Matter? An energy source is “renewable” when supplies of it never run out and “non-renewable” when one day they will run out. which energy sources on your list are renewable and which are non-renewable? DiscussWindmills, renewable.What? Renewable?Wind energy is used as power to produce electricity .
A coal power station , non-renewable.What? Renewable?The Coal power stations where electricity is produced by burning coals.An oil refinery(精炼厂), non-renewable.What? Renewable?The Oil refineries in which oil is refined and made pure. A nuclear power plant, non-renewable.What? Renewable?A nuclear power plant is designed to change nuclear energy into electricity. Solar panels, renewable.What? Renewable?Solar panels are used to collect solar energy, making electricity or your house warm or heating your water, etc.A hydro-electric dam(水电站), renewable.What? Renewable?The hydro-electric dams are used to keep back water and raise its level for irrigation or for producing electricity, etc.What source of energy?Geysers(间歇泉)What about the weather?
9℃ / 14℃We need…The sun. How about the plants?What are these buildings made of and what is their purpose?
They are made of glass which traps the heat from the sun, making the air warm so that plants can grow better.The earth is trapped in the greenhouse and becoming warmer and warmer How has this come about and does it matter?During the 20th century the temperature of the earth rose about one degree Fahrenheit.Sophie ArmstrongShe works for Earth Care.
She is exploring these questions and writing a magazine article. List two different attitudes among scientists towards global warming. main ideaPart1 (para1)Introduce a debate over the issue of global warming.Part 2 (para2- 3)Part 3 (para4-8)Part 4 (para9)Illustrate how global warming comes about.It’s up to readers to think and decide whether people should do something about global warming or not 4 partscome about 发生;造成happen, take place (尤指以难以防止或预料的方式) No one knows how the accident had come about.
没人知道这次事故是怎样发生的.相关短语:
come across:偶然遇见
I came across some old pictures.
come along: 一起来; 进展; 偶然出现
He came along with me.
come out: 在(天空)出现;(花)开放;(消息)传开; 有…结果
It was dark and the stars were coming out.
come to: 合计;参加(活动); 碰到;有…意义;谈到
The money comes to 100 yuan.
come up with: 追上; 提出; 想出
He usually comes up with some good ideas.
1.True or False:
a. The temperature last century shows that the earth is becoming warmer.
b. Everyone believes that global warming is caused by the activities of humans.
Part 1TFLook at Graph12. What does graph 1 show to us?
It shows the global temperature between _____ and ______. The temperature ________ and decreased over this period but on the whole it increased by around _____ degree Fahrenheit. During this time, The earth reach its ________ temperature in about _______ and its highest in 2000. There was a steady increase in the temperature during the ______ years after 1980. We can see from the graph that the earth has become _______ since early last century.
Part 118602000increasedonecoolest191020warmerdecrease:资料P124
补充: vt: decrease spending 削减开支
n: There is a decrease (of 20%) in size.
尺寸减少了(20%).资料P124steady: 形容词/感叹词walk at a steady pace: adj.均匀的;稳固的
Keep the camera steady. adj.不摇晃的
He has made steady progress. adj.平稳进行的持续的,逐渐的
a steady worker adj.可靠的
a steady job/boyfriend/relationship adj.稳定的
Steady!/Steady on! v.当心点,慢着!
1.True or False:
a. Janice Foster believes that
global warming is caused by
burning fossil fuels.
b. Natural gas is a greenhouse gas.
c. Carbon dioxide is a byproduct of burning fossil fuels.
Part 2TFTby-: 次要的
byproduct: 副产品
bystander: 旁观者;局外人2. How has global warming come about?
①Human activity--- some byproducts made by the burning of__________.② Greenhouse effect--- greenhouse gases like _____________ __________ and ____________.③ Huge quantities of extra carbon dioxide means that more heat energy is ________ in the atmosphere causing the temperature to go up.fossil fuelsmethanecarbon dioxidewater vapourtrapped地球自身的温室效应大量的二氧化碳等温室气体不断吸收热量, 地球温度快速攀升.人为加剧温室效应3. What does graph 2 show to us?
It shows the amount of _____________ in the atmosphere from ______ to 1997. The carbon dioxide content _________ steadily over this 40-year period from around _______ to _________ parts per million.
carbon dioxide1957went up330365 1.True or False:
a. People accept Charles Keeling’s data because he took accurate measurements.
b. Flooding could be one of the effects of future global warming.
c. Geroge Hambley believes scientists are just guessing about the effects of global warming.
d. George Hambley is worried about the effects of caron dioxide on plant growth.
Part 3TTTF2. The different ideas between Dr. Janice Foster & George Hambley*rising of sea levelcatastrophe very seriouspositive*produce more crops*make plants grow
faster*severe storms*droughts*spread of diseases*destruction of species*encourage a greater range of animalsrange : n./v.1.an interesting range of books: (n. 批; 组; 类)
2.We have students from a wide range of backgrounds.我们的学生来自各种不同的背景.
3.The ship is now within range of enemy.
(n.在可拿到; 听到的范围为内) 该船已进入敌区.
4.There are 70 students whose ages ranged from 16 to 19. (v. 价格;温度;水平等处于某范围内.) 有70名学生,年龄在16到19岁之间. 1.True or False:
a. It is clear what the effects of global warming will be.
b. Greenhouse gases continue to build up and the climate is going to keep on warming .
2.What do you think
we should do ?
Part 3FT资料P123资料P123build up: 逐渐增强;增加;汇集; 积累They are building up heir forces.
他们在集结军队.
He has built up a good business.
他已使他的生意兴隆起来.
He soon built up his health.
他很快恢复了健康.What will it be tomorrow?Explanation
由it引导的强调句结构：
It is (was) + 被强调部分+ that (who) + 句子其他部分
注意：此结构可强调句子的主语，宾语, 表语(名词), 和状语。如：
It was my father who/that did the experiment in the lab yesterday evening．原句：My father did the experiment in the lab yesterday evening．主语宾语地点状语时间状语强调主语： It was the experiment that my father did in the lab yesterday evening．
It was yesterday evening that my father did the experiment in the lab．原句：My father did the experiment in the lab yesterday evening．主语宾语地点状语时间状语强调宾语：强调时间状语： It was in the lab that my father did the experiment yesterday evening．
强调地点状语：原句：My father did the experiment in the lab yesterday evening．主语宾语地点状语时间状语注意其他形式:
1. It was not until he told me that I knew the truth．
2. It is only then/at that time that the rainbow appears.
3. It was only when the bell rings that we realized the class was over.
4. Was it the man who/that stole the bike?
Was it because of the bad weather that the plane was put off?选词填空: quantities of fuels phenomenon compared to1.The temperature of the earth is rapidly increasing __________ most natural changes.
2. People have caused the increase in the earth’s temperature through the burning of fossil ________ .
3. There is a natural _____________ that scientists call the “greenhouse effect”.
4. The problem begins when we add huge
__________ carbon dioxide to the atmosphere. compared tofuelsphenomenonquantities of选词填空: results in catastrophe measurements consequence data 5. Charles Keeling collected some ________ and made accurate _____________ of the amount of carbon dioxide in the atmosphere.
6. It is the burning of more and more fossil fuels that _________ the increase in carbon dioxide.
7. An increase of five degrees would be a _________.
8. The ___________ of a rising sea level would be widespread flooding(洪水泛滥).
. measurementsresults incatastropheconsequencedata典型例题分析：
1) It was last night ____ I saw the film Star Wars．
A．who B．when
C．that D．which答案C 强调句的结构是：It + be + 强调部分 + that (who) +主谓句。强调句的连词只有两个，that和who。当强调的部分是人，且为句子的主语时，才用who，其余用that。2) It is ten years ____ Miss Green returned to Canada．
A．that B．when
C．since D．as
答案 C考点是连词用法。本题易误选为A 其实本句不是强调句。 若是去掉It be…that还应是一个完整的句子。而本句去掉‘It is…that, 只剩下ten years Miss Green returned to Canada 不成句。因此本句不是强调句。It is + 时间+since...，其中 is = has been.1. It was this village ___ I was bought.
A. where B. that
C. on which D. which练习:2. It was in this village ___ I was bought up.
A. where B. that
C. on which D. which3. --- Was it under the tree ___ you were away talking to a friend?
--- Sure. But when I got back there, the bike was gone.
A. that B. where
C. which D. whilelightheatingtelevisioncassette playervideo playercomputerfridgestoveWashing machinehairdryercoaloilnatural gaswind (wind power)sun (solar energy)uranium (nuclear energy)water (hydro-electric power)plant waste (biomass energy)hot spring or geysers (geothermal energy)the sea (tidal energy)non-renewablenon-renewablenon-renewablerenewablerenewablenon-renewablerenewablerenewablerenewablerenewableWhat are fossil fuels?Ancient animal and plant material below the surface of the earth with a high carbon content, such as coal, oil and natural gas, which can be burnt to produce energy. Also known as non-renewable energy because once they are used they have gone forever; they cannot be renewed.
