问题 名词解释

映象

答案

参考答案:

映象指的是两个层次之间的对应关系。在数据库的层次结构中,通过概念视图/内视图的映象保证数据的物理独立性,通过外视图/概念视图的映象保证数据的逻辑独立性。

阅读理解

“Cool” is a word with many meanings.Its old meaning is used to express a temperature that is a little bit cold.As the world has changed,the word has had many different meaning.

“Cool” can be used to express feelings of interest in almost anything.When you see a famous car in the street,maybe you will say,“It’s cool.”You may think,“He’s so cool,”when you see your favourite footballer.

We all maximize(扩大) the meaning of “cool”.You can use it instead of many words such as “new” or “surprising”.Here’s an interesting story we can use to show the way the word is used.A teacher asked her students to write about the waterfall(瀑布)they had visited.On one student’s paper was Just the one sentence,“It’s so cool.Maybe he thought it was the best way to show what he saw and felt. But the story also shows a scarcity(缺乏)of words.Without “cool”,some people have no words to show the same meaning.So it is quite important to keep some credibility(可信性).Can you think of many other words that make your life as colourful as the word “cool”? I can.And I think they are also very cool.

小题1:We know that the word “cool has had ________.

A.only one meaning     B.no meanings    C.many different meanings   

小题2:In the passage,the word “express” means “________”.

A.see                 B.show          C.know     

小题3:If you are _______ something,you may say,“It’s cool.”

A.interested in          B.angry about       C.afraid of          

小题4:The writer takes an example to show he is ________ the way the word is used.

A.pleased with          B.strange to        C.worried about       

小题5:In the passage,the writer suggests(暗示)that the word “cool”________.

A. may not be as cool as it seems

B. usually means something interesting

C. can make your life colourful

多项选择题