Question

   Have you ever heard someone use the phrase “once in a blue moon”？People use this expression to describe something that they do not do very often. For example,someone might say that he tries to avoid eating sweets because they are unhealthy,but will eat chocolate “once in a blue moon”. Or someone who does not usually like to go to the beach might say “ I visit the shore once in a blue moon. ” While many people use this phrase,not everyone knows the meaning behind it.

   The first thing to know is that the moon itself is never actually blue. This is just an expression. The phrase “blue moon” actually has to do with the shape of the moon,not the color.

   As the moon travels around the earth,it appears to change shapes. We associate (联系) certain names with certain shapes of the moon. For example,when we can see a small part of the moon,it is called a crescent moon. A crescent is a shape that looks like the tip of a fingernail. When we cannot see the moon at all,it is called a new moon. When we can see the entire moon,it is called a full moon. Usually,there is only one full moon every month. Sometimes,however,there will be two full moons in one month. When this happens,the second full moon is called a “blue moon”.

   Over the next 20 years,there will only be 15 blue moons. As you can see,a blue moon is a very rare event. This fact has led people to use the expression “once in a blue moon” to describe other very rare events in their lives.

1. A blue moon will happen in nature .

   A. when there are two full moons in one month

   B. when the moon has a blue color

   C. when we cannot see the moon at all

   D. when we can only see a small part of the moon

2. As described in Paragraph 3 ,what is another example of something that has a crescent shape?

   A. Your thumb. B. A distant star.

   C. The letter “C”.   D. The letter “O”.

3. According to the last paragraph,over the next 20 years,how often will a blue moon happen?

   A. Once a year.

   B. Less than once a year.

   C. More than once a year.

   D. Not enough information is provided.

4. In the last paragraph the author writes “a blue moon is a very rare event” to .

   A. answer an earlier question

   B. provide an example

   C. support the following conclusion

   D. challenge the above statement

5. Which of the following would be a good example of someone doing something “once in a blue moon”？

   A. Mary likes to go to the mountains every weekend.

   B. Tom seldom remembers to take out the trash.

   C. Cindy hates to wash the dishes. However,she does it every day.

   D. Ming sometimes forgets to do his homework.

Answer 1

1. A 2. C 4. C 5. B

  本文主要介绍的是一个美国的习惯用语once in a blue moon ,意思是某种事情很少发生，也就是中国人所说的“千 载难逢”。本文为我们详细介绍了这个习惯用语。

1. A细节理解题。由第三段最后的“ Sometimes,however,there will be two full moons in one month. When this happens,the second full moon is called a ‘blue moon’可知，一个月中出现两次满月，第二个满月就 被叫作“蓝月亮”，由此可知正确答案为A项。

2. C词义猜测题。由第三段中间部分的“A crescent is a shape that looks like the tip of a fingernail." 可知， crescent是一种类似指甲尖的形状，也就是月牙形，故 选C项。

3_ B细节理解题。由最后一段第一句“Over the next 20 years,there will only be 15 blue moons. “可知，在未来20年里只有15个蓝月，也就是一年多才有一个蓝月， 故B项为正确答案。

4. C推理判断题。通读全文可知，文章围绕着once in a blue moon这个习惯用语展开说明，作者最后总结它的意思 是事情很少发生，以支持自己的结论。

5. B细节理解题。由文章内容并分析四个选项可知，B项是在描述“汤姆很少倒垃圾”这个事实，故正确答案为B 项。其他三项与题意不符。

avoid v.避免

crescent  n.新月形(物) ；月牙形 

entire adj.全部的，整个的 rare adj.稀有的;珍奇的

障碍句分析

   The first thing to know is that the moon itself is never actually blue.要知道的第一件事是，实际上月球本身从来不 是蓝色的。

   连词that引导表语从句，表语从句放在连系动词之后， 充当复合句中的表语。从属连词that在表语从句中不充当 任何句子成分，也没有任何意义。