[单项选择]A) the moment C) the moment's
B) a moment D) a moment's

[单项选择]His ________change very quickly; one moment he's cheerful, and the next he's complaining about everything.


A. minds
B. moods
C. motives
D. motions

[单项选择]"A MOMENT'S INATFENTION CAUSES ACCIDENT" is a self-defeating warning because ______.

[单项选择]"A MOMENT'S INATTENTION CAUSES ACCIDENT" is a self-defeating warning because ______.

[单项选择]"A MOMENT'S INATTENTION CAUSES ACCIDENTS" (Line 2, Para. 1) is a self-defeating warning because ______.

[单项选择]设有如下关系表：
R S T
A B C A B C A B C
1 1 2 3 1 3 1 1 2
2 2 3 2 2 3
3 1 3
则下列操作中正确的是______。
A. T=R∩S
B. T=R∪S
C. T=R×S
D. T=R/S

[单项选择]

Text 2
A moment’s drilling by the dentist may make us nervous and upset. Many of us cannot stand pain.
To avoid the pain of a drilling that may last perhaps a minute or two, we demand the "needle"— a shot of novocaine (奴佛卡因) -that deadens the nerves around the tooth.
Now it’ s true that the human body has developed its millions of nerves to be highly aware of what goes on both inside and outside of it. This helps us adjust to the world. Without our nerves—and our brain, which is a bundle of nerves— we wouldn’t know what’s happening. But we pay for our sensitivity. We can feel pain when the slightest thing is wrong with any part of our body. The history of torture is based on the human body being open to pain.
But there is a way to handle pain. Look at the Indian fakir(行僧) who sits on a bed of nails. Fakirs can put a needle right through an arm, and feel no pain; This ability that some human
A. how to stiffer pain
B. how to avoid pain
C. how to handle pain
D. how to stop pain

[单项选择]whistled B. sung C. showed D. presented


A. showed
B. presented
C. whistled
D. sung

[单项选择]设有关系R(A，B，C) 和S(C，D) 与关系代数表达式
π_A，B，D(σ_R，C=s.c(R×S))
等价的SQL语句是
A. SELECT*FROM R,SWHERE R.C=S.C
B. SELECT A，B，D FROM R，S WHERE R.C=S.C
C. SELECT A，B，D FROM R，S WHERE R=S

[单项选择]假定有两个关系R与S，其内容分别为：
R关系 S关系
A B C B C D
1 2 5 2 5 17
2 5 6 2 5 9
3 5 4 5 4 1
则R∞S的运算结果为________。
A. A B C
B. A B C D
C. A B C S.B S.C D
D. A B C