单选题
Long, long ago, people didn't know what the Milky Way was, so they explained it ______.
【正确答案】
B
【答案解析】解析：因果关系的找寻和判断。根据原文But since they didn't know what it was，they made up all sorts of strange and beautiful conjectures of the Milky Way可知由于当时人们不知道银河是由什么构成的，他们便给银河编造了各式各样瑰丽奇妙的故事。由此可见，选项B的说法与原文意思相符，因此该项为正确答案。
单选题
In early Christian times, people thought the Milky Way to be an opening in the sky for ______.
【正确答案】
B
【答案解析】解析：特定信息的找寻和判断。根据题干中关键词In early Christian times定位到原文相关信息Some imagined it was an opening in the heaven，so that we here on earth could have a glance of the magnificent inside即当时人们以为银河是天堂的开口，这样地上的人们便可有机会瞥一眼天堂里壮观的景象，由此可见B项内容与原文意思相符，该项为正确答案。
单选题
What does the galaxy look like?
【正确答案】
A
【答案解析】解析：事实细节的找寻和判断。根据原文Our galaxy is roughly like a watch，round and flat．If you could get above it and look down on it，it would look like a very large watch可知我们的星系大致像块表，又圆又平。如果你从星系上方向下看，它就像一只巨大的表。由此可见A项内容与原文相符，该项为正确答案。
单选题
For light ______, it takes about 27,000 years.
【正确答案】
C
【答案解析】解析：事实细节的找寻和判断。根据原文For light from the middle point of the galaxy to reach the sun，it takes about 27，000 years可知从星系中点到太阳，光要走上两万七千年。由此可见C项内容与原文相符，该项为正确答案。
单选题
The galaxy turns ______like a wheel.
【正确答案】
D
【答案解析】解析：事实细节的找寻和判断。根据原文The galaxy turns about its center like a wheel可知星系围绕中心转，就像车轮。由此可见D项内容与原文相符，该项为正确答案。