课件74张PPT。Unit 4 Astronomy：the science of the starsA lot of people are interested in astronomy and some of them have made great progress in this field.But what do you know about it? Astronomy is the oldest science known to man.话题导入 Thousands of years ago man looked at the stars and wondered about the heavens.But man was limited by what he could see with his eyes alone. The Greeks studied astronomy over 2,000 years ago.They could see the size，color，and brightness of the stars.They could see their places in the sky.They watched the stars move as the seasons changed.But the Greeks had no tools to help them study the starry heavens.Each new tool added to the field of astronomy，and it helped man reach out into space.Until there were telescopes(望远镜)，man knew little about the moon.They did not know that the planet called Saturn(土星) had rings around it.Their sight was so limited that they could not see all the planets.In the early 1700s，people thought there were only six planets. Before the spectroscope(分光镜) appeared，man did not know what kinds of gases are in the sun or other stars.Without the radio telescope(电望远镜) we did not know that radio noises come from far out in space. Today，astronomy is a growing science.We have learned more in the last fifty years than in the whole history of astronomy.根据上文完成下列各题 1.What is the oldest science known to man according to the passage? _____ 2.What does the underlined word “it”(Line 5，Paragraph 4) probably refer to? _____ 3.What does the passage mainly tell us? _____It is astronomy.Saturn.Science can’t grow fast without modern technology.基础自测 课文预读内容索引要点探究当堂达标Period One Warming Up，Pre--reading & Reading基础自测1. n.天文学 2. n.系统；体系；制度 3. n.宗教；宗教信仰 adj.宗教上的；信奉宗教的；虔诚的 4. adj.猛烈的；激烈的；强暴的 n.暴力；暴行 5. n.大气层；气氛 6. prep.与……不同；不像Ⅰ.重点单词astronomy systemreligion religiousviolentviolenceatmosphereunlike7. adj.基本的；基础的 8. adj.有害的 n.& vt.损害；危害 9. vi.& vt.乘；增加 10. vi.生存；存在 11. adv.因此；于是 12. vt.& vi.(使)迷惑；(使)为难 n.谜；难题fundamentalharmfulharmmultiplyexistthuspuzzleⅡ.重点短语1. 及时；终于 2. 冷却；使变凉；使缓和；平静下来 3. 下蛋 4. 产生；分娩 5. 轮到某人 6. 阻止；制止 7. 依靠；依赖；取决于in timecool downlay eggsgive birth toin one’s turnprevent...fromdepend onⅢ.重点句式What was uncertain until between 4.5 and 3.8 billion years ago when the dust settled into a solid globe. 随后它会变成什么没人能知道，直到38～45亿年前，这团尘埃才慢慢形成了一个固体的球状物。1.be to do...表示将要发生的动作This produced a chain reaction，which . 这就产生了一种连锁反应，使得生命的发展成为可能。2.make＋宾语＋宾补it was to becomemade it possible for life to developOthers， ，were able to live on land as well as in the water. 另一些，被称作两栖动物，既能生活在水中，也能生活在陆地上。3.过去分词短语作后置定语As a result of this，many scientists believe the earth may become _____ _____. 由于这个 ... ...
