第一部分
Para.1
1 since 引導的是原因狀語從句，定語從句we would normally use to describe a scientific phenomenon 修飾先行詞the terms “術(shù)語”
inadequate = not enough
2 句中 “ into which” 以及后面的 “ from which” 兩個都是引導的定語從句，修飾先行詞 a region of space “空間區(qū)域”。如果which 在定語從句中作介詞的賓語，那么這個介詞可以提到從句前，構(gòu)成“介詞+which”引導的定語從句。這里注意兩個搭配 fall into ； escape from
3 A black hole exerts a strong gravitational pull and yet it has no matter.It is only space - or so we think.
a strong gravitational pull 一個很強的引力 = gravity
yet = but 但是
so we think.是倒裝句，“我們認為如此” （ we think so ）
The theory is that some stars explode when their density increases to a particular point； they collapse and sometimes a supernova occurs.From earth， a supernova looks like a very bright light in the sky which shines even in the daytime.Supernova were reported by astronomers in the seventeenth and eighteenth centuries.Some people think that the Star of Bethlehem could have been a supernova.The collapse of a star may produce a White Dwarf or a neutron star - a star， whose matter is so dense that it continually shrinks by the force of its own gravity.But if the star is very large （much bigger than our sun） this process of shrinking may be so intense that a black hole results.Imagine the earth reduced to the size of a marble， but still having the same mass and a stronger gravitational pull， and you have some idea of the force of a black hole.Any matter near the black hole is sucked in.It is impossible to say what happens inside a black hole.Scientists have called the boundary area around the hole the “event horizon.” We know nothing about events which happen once objects pass this boundary.But in theory， matter must behave very differently inside the hole.
第二部分
Para .2
4 The theory…a supernova occurs.此句是復合句：that some stars explode when their density increases to a particular point 是表語從句； when their density increases to a particular point 是時間狀語。
注意to a particular point 是固定搭配表示“達到某一點”
此句講了超新星supernova產(chǎn)生的步驟，注意有四個不及物動詞vi.的用法
explode increase collapse occur
From earth， a supernova looks like a very bright light in the sky which shines even in the daytime.
which 引導定語從句，修飾light
6.Some people think that the Star of Bethlehem could have been a supernova.
有人認為圣誕星可能是一顆超新星。could have + 過去分詞 表示對以前發(fā)生的行為或動作的推測。
I could have told you about it， but I don't remember it now.我可能給你說過這件事，但我現(xiàn)在記不得了。
7.The collapse of a star…a star， whose matter is…gravity.
whose 引導非限定性定語從句，修飾star . 注意 so… that 的用法
8.Imagine the earth…a black hole.
該句的主要結(jié)構(gòu)是“imagine… ， and you …”而“reduced … to marble ”和“having … pull”分別為過去分詞和現(xiàn)在分詞短語作定語，修飾the earth.
mass 質(zhì)量
have some idea 略知一二
For example， if a man fell into a black hole， he would think that he reached the center of it very quickly. However an observer at the event horizon would think that the man never reached the center at all. Our space and time laws don't seem to apply to objects in the area of a black hole. Einstein's relativity theory is the only one which can explain such phenomena. Einstein claimed that matter and energy are interchangeable， so that there is no “absolute” time and space. There are no constants at all， and measurements of time and space depend on the position of the observer. They are relative. We do not yet fully understand the implications of the relativity theory； but it is interesting that Einstein's theory provided a basis for the idea of black holes before astronomers started to find some evidence for their existence. It is only recently that astronomers have begun specific research into black holes. In August 1977， a satellite was launched to gather data about the 10 million black holes which are thought to be in the Milky Way. And astronomers are planning a new observatory to study the individual exploding stars believed to be black holes.
Para. 3
9.For example， …very quickly
本句是表示與現(xiàn)在事實相反的虛擬語氣。主句謂語動詞用would think ， if引導的條件狀語從句謂語動詞用過去時fell .
Para.1
1 since 引導的是原因狀語從句，定語從句we would normally use to describe a scientific phenomenon 修飾先行詞the terms “術(shù)語”
inadequate = not enough
2 句中 “ into which” 以及后面的 “ from which” 兩個都是引導的定語從句，修飾先行詞 a region of space “空間區(qū)域”。如果which 在定語從句中作介詞的賓語，那么這個介詞可以提到從句前，構(gòu)成“介詞+which”引導的定語從句。這里注意兩個搭配 fall into ； escape from
3 A black hole exerts a strong gravitational pull and yet it has no matter.It is only space - or so we think.
a strong gravitational pull 一個很強的引力 = gravity
yet = but 但是
so we think.是倒裝句，“我們認為如此” （ we think so ）
The theory is that some stars explode when their density increases to a particular point； they collapse and sometimes a supernova occurs.From earth， a supernova looks like a very bright light in the sky which shines even in the daytime.Supernova were reported by astronomers in the seventeenth and eighteenth centuries.Some people think that the Star of Bethlehem could have been a supernova.The collapse of a star may produce a White Dwarf or a neutron star - a star， whose matter is so dense that it continually shrinks by the force of its own gravity.But if the star is very large （much bigger than our sun） this process of shrinking may be so intense that a black hole results.Imagine the earth reduced to the size of a marble， but still having the same mass and a stronger gravitational pull， and you have some idea of the force of a black hole.Any matter near the black hole is sucked in.It is impossible to say what happens inside a black hole.Scientists have called the boundary area around the hole the “event horizon.” We know nothing about events which happen once objects pass this boundary.But in theory， matter must behave very differently inside the hole.
第二部分
Para .2
4 The theory…a supernova occurs.此句是復合句：that some stars explode when their density increases to a particular point 是表語從句； when their density increases to a particular point 是時間狀語。
注意to a particular point 是固定搭配表示“達到某一點”
此句講了超新星supernova產(chǎn)生的步驟，注意有四個不及物動詞vi.的用法
explode increase collapse occur
From earth， a supernova looks like a very bright light in the sky which shines even in the daytime.
which 引導定語從句，修飾light
6.Some people think that the Star of Bethlehem could have been a supernova.
有人認為圣誕星可能是一顆超新星。could have + 過去分詞 表示對以前發(fā)生的行為或動作的推測。
I could have told you about it， but I don't remember it now.我可能給你說過這件事，但我現(xiàn)在記不得了。
7.The collapse of a star…a star， whose matter is…gravity.
whose 引導非限定性定語從句，修飾star . 注意 so… that 的用法
8.Imagine the earth…a black hole.
該句的主要結(jié)構(gòu)是“imagine… ， and you …”而“reduced … to marble ”和“having … pull”分別為過去分詞和現(xiàn)在分詞短語作定語，修飾the earth.
mass 質(zhì)量
have some idea 略知一二
For example， if a man fell into a black hole， he would think that he reached the center of it very quickly. However an observer at the event horizon would think that the man never reached the center at all. Our space and time laws don't seem to apply to objects in the area of a black hole. Einstein's relativity theory is the only one which can explain such phenomena. Einstein claimed that matter and energy are interchangeable， so that there is no “absolute” time and space. There are no constants at all， and measurements of time and space depend on the position of the observer. They are relative. We do not yet fully understand the implications of the relativity theory； but it is interesting that Einstein's theory provided a basis for the idea of black holes before astronomers started to find some evidence for their existence. It is only recently that astronomers have begun specific research into black holes. In August 1977， a satellite was launched to gather data about the 10 million black holes which are thought to be in the Milky Way. And astronomers are planning a new observatory to study the individual exploding stars believed to be black holes.
Para. 3
9.For example， …very quickly
本句是表示與現(xiàn)在事實相反的虛擬語氣。主句謂語動詞用would think ， if引導的條件狀語從句謂語動詞用過去時fell .