to arrive in time.相信他会及时到达。 against time争分夺秒地，尽快地
eg. he was working against time.他正争分夺秒地工作。 ahead of time提
前，提早 eg. We completed the work five days ahead of time.我们提前五
nitrogen, water vapour and other gases, which were to make the
earth’s atmosphere.他们最终形成了碳、氮、水蒸气和其它气体，而这
些就构成了地球的大气。【注释：in time (1)迟早, 最后 eg. In time
you'll forget him.你迟早会忘了他的。 (2)及时, 不迟 eg. He is believed
成一个固定的球体。【注释：settle into有头绪, 上正轨 eg. Things
soon settled into shape.事情很快有了头绪。】 The earth became so
violent that it was not clear whether the shape would last or not.地
happened.真巧, 他们全出去了。】 However, according to a widely
accepted theory, the universe began with a “Big Bang” that threw
matter in all directions.然而，根据一个广泛接受的理论，宇宙开始于
家
multiply vi. & vt.乘； gravity n.万有引力；
solar system 太阳系 增加
重力
religion n.宗教；宗教 oxygen n.氧
satellite n.卫星；人
信仰
shellfish n.水生有壳 造卫星
theory n.学说；理论 动物
gentle adj.温和的；文
time 】
What is even more important is that as the earth cooled down,
water began to appear on its surface.更为重要的是：当地球冷却下来
后，水开始在地球表面出现了。【注释：①what is even more important
一次“创世大爆炸”，该爆炸将物质抛向各个方向。【注释：in
all
directions四面八方；各个方向 eg. The birds flew away in all directions
when he fired a salute with a“bang”.当他“砰”的一声鸣礼炮时，鸟飞向各
个方向。】 After that, atoms began to form and combine to create
我马上就回来。 at one time曾经； at a time一次； at the same time同
时，然而，可是；from time to time有时，偶尔
考题： 1. ______， I lost heart in English learning，but my teacher often
然大笑；explode into laughter突然大笑起来；explode into pieces炸得粉
碎。 如：Many people were injured when the boiler exploded.锅炉爆炸
时，许多人受了伤。】 They were in time to produce carbon,
一团尘埃。 What it was to become was uncertain until between 4.5
and 3.8 billion years ago when the dust settled into a solid globe.这
一团尘埃会变成什么还不能确定，直到45亿至38亿年前，这团尘埃才形
whether the shape would last or not.】 It exploded loudly with fire and
rock. “大爆炸”发生时伴有(艳丽的)火焰和岩石。【注释：explode vt. &
vi.使爆炸；爆发 explode with anger勃然大怒；explode with laughter哄
必修三 Unit 4 Astronomy: the Science Of The Stars天文学： 恒星的科学
I．Vocabulary
astronomy n.天文学 acid n.酸
biologist n.生物学家
astronomer n.天文学 reaction n.反应；回应 biology n.生物学
是由what引导的名词从句作主语；that…on its surface是由that引导的名
词从句作表语，系表语从句，在这个表语从句中又含有由as引导的时间
状语从句。②what is more 而且, 此外; 更有甚者 eg. They are going
to get married, and what's more they are setting up in business together.他们
气
人；接着
坠落
atmosphere n.大气 carbon dioxide二氧化 lessen vi. & vt.减少；
层；气氛
碳
减轻
fundamental adj.基本 prevent…from…阻 cheer up 感到高兴；
的；基础的
止；制止
感到兴奋
dissolve vt. & vi.溶 puzzle n.迷；难题 vt. weightlessly adv.失重
said to me，“Keep on studying hard, and you’ll succeed _______.”
A． At a time；in time B．At a time；on time C．At one time；in
time D．At one time；on time
2. —Does he often ask you for help?
No one knows exactly how the earth began, as it happened so
long ago. 由于地球的产生是那么的久远，所以没有人确切知道地球是
怎样产生的。【注释：as it happened 碰巧 eg. They were all out, as it
天完成工作。 all the time一直，始终 eg. I have been busy all the time.我
一直很忙。 at no time绝不，在任何情况下都不 eg. At no time will we
give up.我们绝不屈服。 in no time立刻，马上 eg. I'll be back in no time.
球变得如此剧烈，以致于它能否持续下来还不清楚。【注释：①so…
that…如此…以致于…：eg. The words tumbled out so fast that I could
barely hear them.话说得那么快，我几乎都听不清。 ②it was not clear
whether the shape would last or not.句中的it是形式主语，真正的主语是
stars and other bodies.之后，原子开始形成，并结合形成恒星和其他
物体。
For several billion years after the “Big Bang”, the earth was still
just a cloud of dust.就在“宇宙大爆炸”之后的几十亿年间，地球依然是
—Oh，no，only________.
A．all the time B．at one time C．at a time
D．at
times
3．—I am afraid I can’t return the book to you before Friday.
—
________.
A．Don’t be afraid B．Be careful C．Not at all D．Take your
Big Bang宇宙大爆 amphibian n.两栖动物 雅的
炸；创世大爆炸
reptile n.爬行动物； geologist n.地质学家
atom n.原子
爬虫
physicists n.物理学家
globe n.球体；地球 lay eggs 下蛋
block out 挡住（光
仪；地球
dinosaur n.恐龙
解；解散
& vi.
地
harmful adj.有害的 exhaust vt.用尽；耗尽； mass n.质量；团；
get the hang of熟悉； 使精疲力竭
掌握；理解
cabin n.小屋；船舱
块；大量 now that 既然
break out突发；爆发
watch out密切注意；
当心；提防
II．Reading HOW LIFE BEGAN ON THE EARTH 地球上 的生命是怎样开始的
water was to be fundamental to the development of life.（但），这
并没有立刻就表明：水是生命发展的必要部分。【注释：