问题 单项选择题

第(38)~(40)题,基于“学生-选课-课程”数据库中的3个关系:
S(S#,SNAME,SEX,DEPARTMENT),主码是S#
C(C#,CNAME,TEACHER),主码是C#
SC(S#,C#,GRADE),主码是(S#,C#)

查找每个学生的学号、姓名、选修的课程名和成绩,将使用关系( )。

A.只有S、SC

B.只有SC、C

C.只有S、C

D.S、SC、C

答案

参考答案:D

解析: 依据题意,我们查询涉及到“学号”的字段、“姓名”字段、“课程名称”字段和“成绩”字段,“学号”字段S#和“姓名”字段SNAME隶属于关系S,“课程名称”字段CNAME隶属于关系C,“成绩”字段GRADE属于关系SC,所以涉及到的关系分别为SC、C和S。

阅读理解

阅读理解。

     Everyday, 340 million people speak it. One billion people are learning it and it is said that by 2050,

half of the world's population will be using it. What are we talking about? That global language-English.

     The English language started in Britain in the 5th century. It is a mixed language. It was built up when

German. Scandinavian and French invaders settled in England and created a common language for

communication.

     Today it is the official language of the UK, the USA, Australia, New Zealand, Canada, South Africa

and Ireland as well as many islands in the Caribbean . Many other countries and regions use it for politics

and business, for example, India. Pakistan, Nigeria and the Philippines. English is also one of the official

languages of Hong Kong.

     But global advertising and pop music mean that in most countries, you will see or hear some English.

Thanks to McDonalds, we all know about "burgers". "fries" and "milkshakes". Songs by Madonna,

Britney Spears and Celine Dion are in English. We can sing along, even if we do not understand what

we are singing!

     English is a messy (杂乱的) language. Every year, dictionaries include new words that talk about

popular culture, for example, computer-related words such as "blogging", "download" and "chatroom".

Also included are words that teenagers use. Who does not know "cool", "OK" and "hello" ?

     Other languages also influence English. Many English words come from French. Words like "cafe"

and expressions like "c'est la vie" (that is life) are all part of the English language. On the other hand, the

French language includes English words like "le weekend" and "le camping". German words are also part

of English. Words like "kindergarten" come from the German language.

     Recently, British people have become interested in "yoga". But the word comes from an ancient Hindu

language in India.

1. The English language has a history of  ______.

A. over 2000 years

B. over 500 years  

C. over 1500 years

D. over 1000 years

2. The underlined expression "thanks to " can be replaced by ______.

A. because of

B. thankful to    

C. not until

D. as if.

3. Which of the following statements is true about the language of English ?

A. It has been changing all the time.

B. It has borrowed words from all the other languages.

C. French words are used by the English because dictionaries have French words.

D. Singers and film stars have the greatest influence on language.

4. How many people in the world are using English now?

A. One billion people                

B. 340 million

C. almost all the people in the world.

D. not mentioned above, but the number is growing rapidly.

5. Many countries and regions use it for politics and business except______.

A. the USA    

B. Nigeria      

C. the Philippines    

D. Norway

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