课件41张PPT。Unit 4Unit 4
Astronomy:
the science of the stars1. To listen to a text and learn about gravity
2. To read a passage about “a visit to the moon” and summarize the main idea Isaac Newton 1642～1727 英国物理学家 经典物理学理论体系的建立者1665年创立微分；1666年开始研究积分。1666年, 开始想到研究重力(gravity)问题，苹果落地的传说，也是在此时发生的轶事。其一生的重大科学思想是在这两年期间（22至23岁）形成的。1669年，把《自然哲学的数学原理》，《宇宙体系》等手稿送到剑桥大学图书馆收藏。晚年研究宗教。Albert Einstein (1879～1955) 质量(m)和能量(E)的相当性：E＝mc2
爱因斯坦在量子论、分子运动论、相对论(Theory of Relativity)等物理学的三个不同领域取得了历史性成就，特别是狭义相对论的建立和光量子论的提出，推动了物理学理论的革命，他对社会进步事业也有重要贡献。Stephen Hawking (1942～2018) 斯蒂芬·藿金是当今科学界的一位
传奇人物。这不仅仅因为他是一位被誉
为继爱因斯坦后最著名的科学思想家和
最杰出的理论物理学家，还在于他是在
常人无法想象的身体状况下进行研究和
创造性工作的。black hole 黑洞 黑洞并非只是吞噬物质。除了会在
星系形成的过程中扮演重要角色外，在
经过一段相当漫长的时间后，黑洞也会
把一些曾被它吸入的物质信息向外界释
放出来。Now we’re going to listen to a talk about the theories of gravity. Listen carefully and try to get the main idea of it.A The text is about how three scientists
wanted to find out about the beginning
of the universe.
B The text is about how the idea of
gravity has developed over a long
period of time.
C The text is about the importance of
three scientists and their work.Choose the best summary.Summary B is correct because it gives a clear idea of what the listening passage is about.
Summary A is not true. The three scientists wanted to explain how the universe worked and not how it began.
Summary C is too general and does not give enough detail about what the listening passage is about.Listen to the tape again and fill in the chart.Large bodies have a force which pulls things towards them.In space large objects make space and time bend; the larger the object, the further space and time bend.Black holes have a very large mass and pull things towards them.The bigger the object the stronger the gravity.Time goes slower in very strong gravity.If you go over the edge, you cannot get out; but if you do not, you may be able to escape.MJ: Hello, Dr Li Yanping. It’s so good of
you to talk to me. Some _______ ask us
why things always fall back to _____ if
you throw them up in the air. Could
you ________ it?
LY: Well, at first people thought it was
because the earth was the ______ of the
universe. Of course that was ______.
One day Isaac Newton watched an ____Listen again and fill in the blanks.studentsearthexplaincentrewrongapple fall to the ground. He said that
something else must be ______ the apple
back to earth. He called it “gravity”.
MJ: I see. Did people _______ his idea?
LY: They did. Later they worked out that
bigger _______ (like the sun) have
stronger gravity than _______ objects
(like our planets). If you’re travelling in
____ space, you couldn’t fall back to the
earth. You’re just too far ______.pullingacceptobjectssmallerdeepawayMJ: Does it mean there’s no ______ in space?
LY: No. In a spaceship you would feel the
pull as it got ______ to such an object.
You would travel faster and faster
________ it.
MJ: Until you hit it?
LY: Not exactly. You may _____ it very fast
and then it would throw you out into
space again. After that you would slow
down to the _____ speed.Part 2gravityclosertowardspassusualMJ: How do you know this?
LY: In ____ Einstein said that in space large
objects make space-time bend; the
larger the object, the ______ space-time
bends. So time goes ______ in very
strong gravity.
MJ: What about ______ holes?
LY: That’s a place in space which has such
a strong ______ that nothing can escape
____ its gravity. There is a kind of edge 1905furtherslowerblackmassfromaround this mass. If you cross over this edge, it’s _________ for you to get back. However if you don’t cross this edge, you can still ______. Stephen Hawking has done a lot of ________ into black holes. He has shown that they “spit” things out as _____ as “eat” them.impossibleescaperesearchwellspacewalkLook at the pictures! Read the passage carefully and then describe the three ways in which gravity changed for Li Yanping and how his weight changed.1. The pull of gravity became very strong as he left the earth’s atmosphere. His weight is normal.2. It disappeared when he was in space. He is weightless.3. It was very light when he was on the
moon. He weighs less than on earth.1. ... “walking does need a bit of practice now that gravity has changed.”
......既然引力改变了，走路也的确需要练一练了。 now that同since相似，语气较弱，强调人们已知的事实。Translation.
1) 既然你忙, 就让我给你做吧。
Now that you are busy, let me do it for
you.
2) 既然人都齐了, 咱们开始干吧。
Now that everyone is here, let’s start
work.2. We watched, amazed as fire broke out on the outside of the spaceship as the earth’s gravity increased.
我们惊奇地看着，随着地球引力的增加，宇宙飞船的外层燃烧起火。【归纳】?
break out?意为“爆发，突然开始”，常指战争、灾难或打斗等不愉快事件的发生。如：
The Second World War broke out in September 1939.
A fire broke out in this hotel last night.
I was in a club in Brixton and a fight broke out.【拓展】?
常见的含break的短语还有：
break down （机器或车辆）出故障，坏
掉
break into 强行闯入
break off 突然停止，中断
break up 结束；打碎；分开，解体【语境运用】?用含break的短语的正确形式填空。
1) We are sorry to arrive late, but the car ____________.
2) I was still living in?London?when the war ____________.
3) We had to ____________ the house as we had lost the key.
4) He _____________ the chocolate and gave each child a small piece.broke down?broke out???break intobroke up??5) They were arguing but ___________ when someone came into the room.
6) Does everyone know what to do if a fire ___________?broke off?? ??breaks outI.?根据下面各句句意以及所给单词的首字母或汉语提示词，写出该单词的正确形式（每空一词）。
1. You can f________ very easily on the?Dead Sea?because it’s so salty.
2. A s________ is designed to carry people through space.
3. She gave a gentle ________ (拉) on the rope, and the bell rang.float?spaceshippullII.?选用方框内合适的短语并用其正确形式填空（每个短语限用一次）。
1. ______________ cars when you cross the street.
2. The old man runs fast __________ he were a young man.
3. She tried to _____________ the disappointed boy who failed to win the game.as if, now that, cheer up, break out, make sure, watch out forWatch out foras if?cheer upas if, now that, cheer up, break out, make sure, watch out for4. ____________ I could not stay here anymore, I prepared to leave.
5. Other reports said the fire ____________ on a city bus at about 8:30 am as it passed near the zoo.
6. When he ____________ that no one was noticing him, he jumped into the room through the open window.Now thatbroke outmade sureCollect passages about gravity.
Prepare for speaking.
