1、Unit 4 Astronomy:the science of the stars众所周知，天文学是一门古老的学科。随着科技的发展，人类对天体的认知亦越发深入！Astronomy is the oldest science known to man.Thousands of years ago man looked at the stars and wondered about the heavens.But man was limited by the six planets that he could see with his eyes alone.The Greeks studied a
2、stronomy over 2，000 years ago.They could see the size，colour，and brightness of a star.They could see its place in the sky.They watched the stars move as the seasons changed.But the Greeks had no tools to help themselves study the heavens.Each new tool added to the field of astronomy helped man reach
3、 out into space.Until there were telescopes，man knew a little about the moon.He did not know that the planet called Saturn had rings around it.His sight was so limited that he could not see all the planets.Before the spectroscope，man did not know what kind of gases was around the sun or other stars.
4、Without the radiotelescope，we did not know that radio noises came from far in space.Today，astronomy is a growing science.We have learned more in the last fifty years than in the whole history of astronomy.阅读障碍词1tool n工具2telescope n望远镜3Saturn n土星4spectroscope n分光镜5radiotelescope n射电望远镜诱思导读 1Astronomy
5、 is the oldest science known to man.()2We know more about the field of astronomy with the development of technology.()答案 1.T 2.TSection Warming Up，Prereading&Reading新 生 词 汇 初 识.匹配下列单词的词性及汉语意思()1.astronomy An.学说；理论()2.systemBadj.猛烈的；激烈的；强暴的()3.theory Cn.大气层；气氛()4.violentDadj.基本的；基础的()5.atmosphere Evi
6、.&vt.乘；增加()6.fundamental Fn.&v.谜；(使)迷惑()7.harmful Gvi.存在；生存()8.multiply Hadj.有害的()9.exist In.天文学()10.puzzle Jn.系统；体系；制度答案 15 IJABC 610 DHEGF.选出下列句中词组的汉语意思A下蛋 B及时；终于 C阻止；制止 D轮到某人 E产生；分娩 F对来说是基本的()1.The truth will come to light in time.()2.As we know，laying eggs is the ant queens full-time job.()3.Onc
7、e she has made up her mind，nobody can prevent her from carrying out the plan.()4.When it was in my turn，I was too excited to speak.()5.Jane has just given birth to twins，so her mother must be in the hospital looking after her now.()6.My relationship with the actors is fundamental to my work as a dir
8、ector.答案 16 BACDEF教 材 语 篇 细 研 HOW LIFE BEGAN ON THE EARTHNo one knows exactly how the earth began，as it happened so long ago.However，according to a widely accepted theory，the universe began with a“Big Bang(宇宙大爆炸)”that threw matter in all directions.After that，atoms(原子)began to form and combine to cr
9、eate stars and other bodies.地球上生命的起源没有人确切知道地球是怎样开始形成的，因为在很早以前它就形成了。然而，一种普遍为人们所接受的理论是：宇宙起源于一次大爆炸，这次大爆炸将物质投射到四面八方。然后，原子开始形成并结合成恒星和其他天体。助读讲解 how引导宾语从句，as引导原因状语从句。begin with从开始，起源于。in all directions朝四面八方。For several billion years after the“Big Bang”，the earth was still just a cloud of dust.What it was t
10、o become was uncertain until between 4.5 and 3.8 billion years ago when the dust settled into a solid globe.The earth became so violent that it was not clear whether the shape would last or not.It exploded loudly with fire and rock.They were in time to produce carbon dioxide(二氧化碳)，nitrogen(氮)，water
11、vapour and other gases，which were to make the earths atmosphere.What is even more important is that as the earth cooled down，water began to appear on its surface.大爆炸后好几十亿年过去了，但地球还只是一团尘埃。随后它会变成什么没人能知道，直到3845亿年前，这团尘埃才慢慢地形成一个固体的球状物。地球(开始)变得激烈动荡，不知道这个固体形状是否会继续存在下去。它(地球)猛烈的爆炸喷出了烈火与岩石，它们最终产生了碳、氮气、水蒸气和其他多种
12、气体，从而形成了地球的大气层。更为重要的是，地球冷却了下来，地球的表面就开始出现了水。助读讲解 it作形式主语，whether从句为真正的主语。in time to do sth./for sth.及时做某事。Water had also appeared on other planets like Mars but，unlike the earth，it had disappeared later.It was not immediately obvious that water was to be fundamental to the development of life.What ma
13、ny scientists believe is that the continued presence(存在)of water allowed the earth to dissolve(溶解)harmful gases and acids(酸)into the oceans and seas.This produced a chain(连锁)reaction(反应)，which made it possible for life to develop在火星这些其他行星上都出现了水，但和地球不同的是，这些水后来都消失了。水对于生命的发展会起关键作用，这一点在当时并不明显。很多科学家相信，由于
14、地球上长期有水存在，使地球得以把有害气体和酸性物质溶解在海洋里。这就产生了一系列的反应，使得生命就有可能开始发展了。助读讲解 be fundamental to 是的基础。which引导非限制性定语从句，修饰a chain reaction。Many millions of years later，the first extremely small plants began to appear on the surface of the water.They multiplied and filled the oceans and seas with oxygen(氧)，which encou
15、raged the later development of early shellfish and all sorts of fish.Next，green plants began to grow on land.They were followed in time by land animals.Some were insects.Others，called amphibians(两栖动物)，were able to live on land as well as in the water.Later when the plants grew into forests，reptiles(
16、爬行动物)appeared for the first time.They produced young generally by laying eggs(下蛋)After that，some huge animals，called dinosaurs，developed.They laid eggs too and existed on the earth for more than 140 million years.However，65 million years ago the age of the dinosaurs ended.Why they suddenly disappear
17、ed still remains a mystery.This disappearance made possible the rise of mammals(哺乳动物)on the earth.These animals were different from all life forms in the past，because they gave birth to young baby animals and produced milk to feed them.好几百万年以后，水的表面开始出现了极小的植物。它们繁殖起来就使得海洋充满了氧气，这为早期的贝类及其他各种鱼类后来的进化创造了条件
18、。接着，绿色植物开始出现在陆地上。随后，陆地上出现了动物，其中有一些是昆虫，另外一些叫两栖动物，它们既能在陆地上生活，也能在水里生存。后来，当植物长大成了森林的时候，爬行动物出现了。它们一般是通过孵蛋而繁衍后代的。再后来一些叫作恐龙的巨型动物出现了。它们也生蛋，在地球上生存了一亿四千多万年。然而，六千五百万年前，恐龙时代结束了。它们为什么会突然灭绝至今仍是个谜。恐龙的灭绝使地球上哺乳动物的增多有了可能。哺乳动物不同于以往所有的生物形式，因为它们能从体内生产出幼仔并给幼仔哺乳。助读讲解 encourage vt.鼓励，鼓舞，促进，激发。called amphibians作后置定语。why引导主语
19、从句。Finally about 2.6 million years ago some small clever animals，now with hands and feet，appeared and spread all over the earth.Thus they have，in their turn，become the most important animals on the planet.But they are not looking after the earth very well.They are putting too much carbon dioxide int
20、o the atmosphere，which prevents heat from escaping from the earth into space.As a result of this，many scientists believe the earth may become too hot to live on.So whether life will continue on the earth for millions of years to come will depend on whether this problem can be solved.最后，大约260万年前，一些小巧
21、聪明、长着手脚的动物出现了，它们散布在地球的各个地方。于是，他们接着成了这个行星上最重要的动物。然而，他们对地球却不怎么在意，他们把过多的二氧化碳释放到大气层中，这使得地球上的热不能释放到太空中去。因此许多科学家相信地球可能会因此变得太热而不适合生物的生存。所以，在未来的数百万年中，生命能否在地球上延续取决于这个问题能否得到解决。助读讲解 as a result of 由于too.to.太而不能depend on取决于，依靠。第一步 速读了解文章主题和段落大意.速读P2526教材课文，匹配段落大意/选择最佳答案1Para.1 AThe formation of the earth.2Para.
22、2BA widely accepted theory about the formation of the universe.3Para.3 CThe development of plants and animals on the earth.4Para.4DThe arrival of humans and their impact on the earth.5Para.5 EThe importance of water for life.答案 15 BAECD6What does the passage mainly tell us?AThe importance of water.B
23、How the life began on the earth.CHow human beings appeared.DHow plants appeared.答案 B第二步 细读把控文章关键信息 细读P2526教材课文，选择最佳答案1.Why was life able to develop on the earth but not on other planets?AThe earth had a solid shape.BThe earth did not have harmful gases in its atmosphere.CThe water stayed on the eart
24、h but not on other planets.DThe earth was neither too hot nor too cold.2Why was it necessary for plants to grow before animals?AAnimals needed plants to protect them from the sun.BPlants provided oxygen for animals to breathe.CAnimals could hide from hunters in the forest.DIt was easier for plants t
25、o grow.3Why did dinosaurs disappear 65 million years ago?ABecause the earth was too hot for them to live on.BBecause there was no food for them to eat.CBecause the earth exploded at that time.DIt still remains a mystery for us.4What problem is caused by human beings?AThey exist everywhere on the ear
26、th.BThey cause global warming.CThey find new methods of growing crops.DThey enjoy hunting and fishing.答案 14 CBDB第三步 研读能力升华，接轨高考根据P2526教材课文，在空白处填入1个适当的单词或括号内单词的正确形式The earth was just 1._ cloud of dust after the“Big Bang”The earth exploded 2.(loud)with fire and rock.They were in time to produce many t
27、hings，which were 3.(make)the earths atmosphere.As the earth cooled down，water began to appear on its surface.It allowed the earth to dissolve 4.(harm)gases.Then life began to develop.aloudlyto makeharmfulSmall plants multiplied and filled the oceans and seas with oxygen.This encouraged the 5.(develo
28、p)of early shellfish and fish.Land animals such as insects，reptiles and dinosaurs 6._(appear)after green plants appeared.Small clever animals spread all over the earth.They are putting too much carbon dioxide into the atmosphere，7.prevents heat from 8.(escape)from the earth into space.9.life will continue on the earth for millions of years to come will depend on whether this problem can 10._(solve)developmentappearedwhichescapingWhetherbe solved点击右图进入 课 时 分 层 作 业 Thank you for watching!