1、 Unit 4AstronomyWhats the meaning of the word “Astronomy”?I. Warming up行星the science of stars;2. Do you know the following terms? star, planet, the sun / moon / earth, solar system太陽系 3. How many planets are in the solar system? 8恒星PlutoScientists now think Pluto is too small to be called a planet.4

2、. Do you know the correct order of their distance to the sun? nearest to the sun? farthest to the sun?5. The names of eight planets.MercuryVenusEarthMarsJupiterSaturnUranusNeptune1) 水星2) 金星3) 地球4) 火星5) 木星6) 土星7) 天王星8) 海王星In this unit, well learn something more scientific.1.Whats the title of the tex

3、t?2. From the title, we can predict that the text may tell us the origin of life on the earth.Do you know some stories about it?How life began on the earthPangu separates the sky from the earth. Nvwa made humans.Fast readingI. Read the passage and match the main idea with each paragraph. Para. 1 The

4、 formation (形成) of the earth.Para. 2 The importance of water for life.Para. 3 A widely accepted theory about the formation of the universe.Para. 4 The arrival of humans and their impact on the earth. Para. 5 The development of plants and animals on the earth.1. When did the “Big Bang” happen?Read th

5、e passage quickly and answer the questions.2. What form was the earth after the “Big Bang”?3. What made up the earths atmosphere4. How did water come into being on the earth?5. Whats the significance of the presence of water on the earth?6.What was important to the development of fish?7. What made p

6、ossible the rise of mammals on the earth?8. Why are mammals different from all life forms in the past?1. When did the “Big Bang” happen? It happened several billion years ago.Scanning Read the passage quickly and answer the questions.2. What form was the earth after the “Big Bang”? The earth was sti

7、ll just a cloud of dust.3. What made up the earths atmosphere after the earth exploded? Carbon, nitrogen, water vapour and other gases. 4. How did water come into being on the earth? As the earth cooled down after it exploded, water came into being.5. Whats the significance of the presence of water

8、on the earth? It allowed the earth to dissolve harmful gases and acids into the oceans and seas.6. What was important to the development of fish? oxygen. 7. What made possible the rise of mammals on the earth? The disappearance of dinosaurs made the possible the rise of mammals on the earth.8. Why a

9、re mammals different from all life forms in the past? They gave birth to young baby animals and produced milk to feed them.Finish the Exercise 2 on the book according to the questions above. Detailed readingStage 1 : The development of the earthStage 2 : The development of life(para 13)(para 45)Stag

10、e 1: The development of the earth(1) After the Big Bang, what was the earth like? a cloud of dust a solid globe exploded with fire and rock produced water vapour and gases(2) What happened next?(3) What did the water vapour and gases form?the earths atmosphere Water appeared(4) What appeared as the

11、earth cooled down?water is important for the beginning of life on the earth. Why is water so important for the beginning of life? Because water allowed the earth to dissolve harmful gases into oceans and seas.？Stage2 The development of life small plants appears in water 1.What life developed after w

12、ater appeared?Shellfish and all sorts of fish 2.What life developed in water next? green plants began to grow on land insects appeared3.What about the life on land?amphibians on land and in the waterforests4. What life developed next on land? reptiles appeared dinosaur developed 5.What life develope

13、d after forests appeared?mammals on land6.What life developed after dinosaurs? small clever animals7. What life developed after mammals? 1.Who are the small clever animals with hands and feet? 2. Are they taking care of the earth well? Why? ? Because they are putting too much carbon dioxide into the

14、 atmosphere, which prevents heat from escaping from the earth into space.The earth may become too hot to live on .Can you fill in the blanks?23456789101 small plants in watershellfish and all sorts of fish insects reptilesamphibiansmammalsdinosaurs humansplantsanimalsGreen plants on landforests1. In

15、sects and amphibians appeared. 3. The earth became a solid ball.5. Reptiles appeared. 7. The earth was a cloud of dust9. Shellfish and other fish appeared.11. Clever animals with hands and feet appeared2. Dinosaurs appeared. 4.Small plants grew on the water.6. Plants began to grow on dry land.8. Wat

16、er appeared on the earth10. The universe began with a “Big Band”.12. Mammals appeared.831091151741262Can you put the order of development of life into a time line?Ex.2 on P27III. Fill in the blanks in the following form.TimeWhat happenedBig Bang_ began to form and combine to create stars and other b

17、odies.AtomsBetween 4.5 and 3.8 billion years agoDust settled into a solid and _ globe.The earth exploded to produce its _.The continued _ of water allowed the earth to dissolve harmful gases and _ into the oceans and seas.violentatmospherepresenceacidsMany millions of years laterThe first small plan

18、ts on the surface of the water produced _.Early _ and all sorts of fish appeared.Green plants began to grow on land. Insects and _ appeared.oxygenshellfishamphibiansMany millions of years later_ appeared and they laid eggs.Dinosaurs developed, laid eggs and _ for more than 140 million years.Mammals

19、rose and _ babies.Reptilesexistedgave birth toAbout 2.6 million years agoSome small _ animals with hands and feet appeared and spread all over the earth.NowHumans produce too much carbon _, making the earth too hot.cleverdioxideIV. True (T) or False (F).1. The earth appeared before the Big Bang happ

20、ened.2. The original atmosphere consisted of nitrogen and oxygen. 3. The main difference between the earth and other planets is that there is water on the earth. 4. Life began in water and then on land.FFTT5. Mammals appeared before the development of dinosaurs.6. Dinosaurs could give birth to young baby animals and produced milk to feed them. 7. Human