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1、UNIT 2Text ABlack HolesI课文简介本文主要介绍了黑洞的概念，黑洞是怎样产生的，以及有关黑洞的一些研究。对于黑洞的研究才刚刚起步，因此黑洞对于我们来说还很神秘，需要我们的不断探索。什么是黑洞？ What is a black hole ?宇宙中有一些点，它们的体积趋向于零而密度变得无穷大。由于具有强大的吸引力，物体只要进入离这些点一定距离内，就会被这强大的吸引力吸收掉，连光线也不例外。因此，没有任何信号能从这个范围内传出，这个范围的边界被称为视界(event horizon) 。视界里面的情况人类无法看到，所以科学家称之为黑洞。一颗燃烧尽了的恒星由于自身的重力而不断塌陷，最
2、后就会形成黑洞。尽管关于黑洞的理论是正确的，但是科学家一直在寻找黑洞存在的证据。课文分为三部分：Paragraph 1 What is a black hole ?Paragraph 2 - paragraph 4 The theory of black holesParagraph 5 Speculations about black holes are endless .II New Words词汇精讲：1 escape v.逃跑，避免A lion has escaped from its cage.一头狮子从笼子里跑出来了2 exert: vt.用尽；尽力；运用；行使；施加，产生（影响等
3、）用法：exert pressure on sb.给施加压力 She exerted herself all year to earn good marks.她整年努力以期获得好分数。Hes been exerting a lot of pressure on me to change my mind.他一直在施加种种压力要我改变主意。Black holes exert very strong gravity.黑洞产生很强的引力。3 explode v.爆炸，突发explosion n.explosive a.A bomb exploded at one of Londons busiest
4、railway station this morning.今天上午一颗炸弹在伦敦最繁忙的火车站爆炸了。4 collapse v.n.倒塌, 崩溃例句 参考教材第34-35页的 word Study 25 shrink: (shrank, shrunk ) v.退缩；畏缩；n.收缩；缩小用法： The gross national product shrank one percent last year.去年国民生产总值减少了1%。Washing wool in hot water will shrink it .在热水中洗羊毛会使它缩水。We will never shrink back be
5、fore difficulties .我们在困难面前决不退缩。shrink+副词/介词短语 ： That sweater shrank in the wash. The girl shrank back in fear.Shrink+名词： This detergent wont shrink wool 这种洗洁剂不会使毛料收缩。6 boundary n.分界线，边界We crossed the state boundary at midnight.我们在午夜穿过了州界。7 constant adj.不断的，经常的；永恒的，始终如一 n.常数He is in constant trouble
6、with the police.他总是不断和警察惹麻烦。There are no constants at all.根本没有不变的事物。 对比同义词：continual 时断时续的 It continually shrinks by the force of its own gravitycontinuous 连续不间断的 The brain needs a continuous supply of blood. 大脑需要不断的供血。 constant强调不变，永恒8 implication: n.牵连；涉及；卷入；含意；暗示派生词：imply v.暗示，含意用法：She seemed by
7、implication to acknowledge that fact.她似乎含蓄地承认了那事实。 The implication of your statement is that I was wrong.你这话的弦外之音是我错了。9basis 基础、根据（复数为bases） His theory has a solid basis in facts. 他的理论有很多事实根据。10 launch: v.发射，发动 n.发射The launch of the third man-made satellite turned to be a great success.第三枚航天器的发射结果是巨
8、大成功。 In the 1980s our country launched a number of satellites.80年代我国发射了多颗卫星。11 convincing : a.令人信服的；有说服力的；派生词：convince v.使人信服，使 相信用法：She is very convincing .她很另人信服。Convince sb.of sth.使某人确信某事； convince sb.that 从句We failed to convince him of his mistakes.我们没能使他相信他是错误的。Careful observation convinced the
9、m that it was so.仔细的观察使他们相信情况是这样的。12 companion : n.同伴，同行，伴侣，同事派生词：company n.同伴，陪伴 ； accompany v.陪同，陪伴用法：He is a good companion on the journey.他是个好旅伴。表示同事的词：associate, colleague, fellow official, fellowworker, co-worker13. speculation 1)speculation+about/on upon+名词： 深思、揣想、推测 He made speculations on t
10、he purpose of life. 他对人生的目的进行深思。 2)peculation +in+名词： 对。投机 Speculation in stocks is a dangerous way of making a fortune. 股票投机是一种危险的发财方式。14swallow 1)swallow+up+名词 ：吞没、吞。 He swallowed up the medicine with water. 2)Swallow+名词： （口语）轻信、忍受 She couldnt swallow his insults.15 operate : v.操作，运行，起作用；动手术派生词：op
11、eration n.操作用法：The machine isnt operating properly.机器运转不正常。He operated on the eyes of the patient.他给病人的眼睛动了手术。Has the medicine started to operate ? 药物开始见效了吗？16result1)result+from+名词 ：由。造成。结果、 由。引起 The terrible accident resulted from his carelessness. 那桩可怕的事故是因他的疏忽大意引起的。2)result+in+名词：导致、引起 His attem
12、pt resulted in failure. 他的尝试终于失败了。17reduce1)reduce+名词：把。减少、下降、减弱 She reduced her weight by 5 kilograms.2)Reduce+名词to+名词/动名词 ：使。变为/成为（可用于被动语态） The bobs reduced the city to ruins炸弹使那座城市变为废墟 She was reduced to tears at the sight. 她看到那情景就哭了起来。 词组：phrases1.to research into 研究She is researching into possi
13、ble cures for AIDS.她正在研究治疗艾滋病的方法。2 speculation about : 关于 的猜测We heard all kinds of speculation about the cause of the Presidents death.我们听到关于总统死亡原因的种种猜测。People have much speculation about the governments intentions.对政府的意图，人们作了许多猜测。3 to swallow up : 吞没；并吞His wifes clothes bill swallowed up his wages
14、.老婆买的衣服耗尽了他的工资。The fog swallowed up the whole city.雾笼罩全城。She swallowed the medicine with the help of some water.她用水把药咽下了。 His figure was swallowed up in the dark.他的身影消失在黑暗中。4 to make use of ：利用= to take advantage of We should make good use of our leisure time.我们应该好好利用休闲时间。 He was making full use of
15、his opportunity.他正充分利用他的机会。to reduce to 简化，归纳，迫使Months bombing reduced the city to ruins.几个月的轰炸使这个城市变成了废墟5 to apply to 适用于It does not apply to you.它不适用于你。III课文详解第一部分Para.11. What is a black hole? 文章开头首先提出问题：What is a black hole? （什么是黑洞？）2. Well, its difficult to answer this question, since the terms we would normally use to describe a sci
