Unit4Reading-ppt课件.ppt
30页
Part One:Lead in What is this?Which planet is its home?This is ChangJiang7.It is an alien（外星的）（外星的） dog from outspace.Can you guess?1 海王星海王星 Neptune水星水星Mercury 金星金星Venus 地球地球Earth 火星火星Mars 木星木星Jupiter 土星土星Saturn天王星天王星Uranus 2 Scientists think Pluto is too small to be called a planet.Goodbye!3 Life is beginning…Unit4 Reading How Life Began on the Earth4 Part Two:A guessing gamesharp eyes, remeber quickly What can you see in the video?5 Big Bangglobeatomviolent surfacewaterreptilealieneggsmammalsfishhuman beingsdinosaurcowboyatmosphere6 Main ideaAfter watching the video clip, what is the main idea of this passage?A brief introduction on how the ______developed and how _____ began on the earth.lifeearth7 Para.1 Para.2Para.3Para.4Para.5 A theory about how the universe （宇宙）（宇宙）was formedThe formation(形成形成)of the earthThe importance of water for lifeThe development of plants and animalsThe arrival of humans and their effects on the earthPart1: The development of _________Part2:The development of________ Part Three:Fast reading the earthlife8 Part Four：Careful ReadingStage 1: The development of the earth(para1-3)Task 1:Fill in the form on learning plan paper. (para1-2)(tips:Read the passage carefully , find some detailed information)9 Time What happened to the earthAfter the Big Bang______ began to form and combine to_______ stars and other bodies.Several billion years after the “Big Bang”The earth was still_______________.Between 4.5 and 3.8 billion years agoDust settled into ___________ .Atomsa cloud of dusta solid globecreate10 Time What happened to the earthNext●The earth began to become___________.●It exploded to _______ C/N, water vapor, etc, which made up__________. As the earth _________________________ began to ___________on its face.violentatmosphereproduceWaterappearcooled down11 Big Bangatom? Atmosphere A solid ballwater学.科.网.A cloud of dust 12 1.Why was the earth different from other plantes?2.Why is water so important for the beginning of life?13 •Task2:•1.Why was the earth different from other plantes?•A . It produced a lot of heat •B . The water remained on the earth•C . A cloud of dust was around the earth•D . It was the oldest planet14 2.Why is water so important for the beginning of life? Because water allowed the earth to dissolve harmful gases into oceans and seas, which made it possible to develop life.15 Task3: Read para(4-5) and put the development of life in time order.(tips:Find out and underline key phrases which can show a time line, such as ...later,...ago)Stage2: The development of the life (para4-5)16 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, which encouraged 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, were able to live on land as well as in the water. Later when the plants grew into forests, reptiles appeared for the first time. They produced young generally by laying eggs. 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 disappeared still remains a mystery. This disappearance made possible the rise of mammals 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. 17 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 into 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. 18 想一想想一想（（ ）） Insects and amphibians appeared.（（ ）） Dinosaurs appeared.（（ ）） Small plants grew on the water.（（ ）） Reptiles appeared.（（ ）） Green plants began to grow on land.（（ ）） Shellfish and other fish appeared.（（ ）） Clever animals with hands and feet appeared.（（ ）） Mammals appeared.1 234567819 Greenhouse effect Task4:What problem is caused by human beings?(para5)putting too much carbon dioxide into the atmosphereprevents heat from escaping from the earthinto spacetoo hot to live on20 Whether life will continue on the earth depends on human beings.Only if we care will we help;only if we help shall all be saved!21 Long long ago, there is an ancientcity called Handan.Handan Congtai 22 Fuyang River23 亲，我是康德，亲，我是康德，我在雾霾中我在雾霾中............24 空气污染，光靠戴口空气污染，光靠戴口罩可不管用罩可不管用............25 26 Part Five: DiscussionDiscuss in groups and give a report to the class.How can we control the air pollution and make our city a better place to live in?27 summary•After the “big bang”, the earth was still just a cloud of _______,it _______loudly with fire and rock, which were _____ to produce the_________, water vapour and other gases. Then ________ began to appear on the earth. dustexplodedin timecarbonwater28 ____________ in water are considered to be the earliest lives on the earth. The oxygen supply encouraged the lives of______________. Slowly_________ grew on land, which were followed by __________like insects & ________. When the plants grew into______, ______ appeared. Then _______ developed but disappeared later, which made the rise of a totally different animal,______, possible, and finally _____ spread all over the world.shell--fish and fishamphibiansforestsreptilesdinosaursmammalhumansThe small plantsland animalsgreen plants29 Goodbye! Many thanks!30 。
