问题 单项选择题

数据库的三级模式结构中,外模式又称为

A.物理模式

B.存储模式

C.逻辑模式

D.用户模式

答案

参考答案:D

解析: 数据库的体系结构通常有三级模式组成,它们是:外模式、模式和内模式。其中外模式又被称为子模式或用户模式。

听力题

根据句意和汉语提示,在空格中填入正确的单词。(每空填一词)

小题1:With his friends' help, he _______ (成功) at last.

小题2:The movie is well ________ (值得)seeing.

小题3:Dick has worked in China since he ________ (毕业) from the college four years ago.

小题4:We shouldn’t spit in _________(公共的).

小题5:Computer is more and more popular now. It has a huge _________ (影响) on our life.

小题6:We should brush our_________ (牙齿) every day.

小题7:China has already carried out the one-child _________ (政策) to control the population.

小题8:To our _______________(惊讶), she left without saying anything.

小题9:This picture is ________________(相似的) to that one.

小题10:Air pollution is ____________(有害的) to people’s health.

小题11:Thanks to their hard work, the environment has _______________ (改善) a lot.

小题12:Michael has made great ___________________(进步) in his study.

小题13:We are ____________ (骄傲的) of our hero.

小题14:Do you learn anything else _______ (除了) Chinese at school?

小题15:Can you _______ (翻译) this English sentence into Chinese?

小题16:________(呼吸) deeply if you are nervous.

小题17:There are several pairs of shoes ________(在……下) the bed.

小题18:Sichuan food is very ________(不同的) from Guangdong food.

小题19:Mr. Green's car was made in ________(德国) in the 1980s.

小题20:________comes after Friday.

小题21:She wants to ________(邀请) some friends to her new house.

小题22:It's cool and the ________ (叶子) fall from the trees in autumn.

单项选择题