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【单选题】
关系模型中,一个候选码是A.
可由多个任意属性组成
B.
至多由一个属性组成
C.
可由一个或多个其值能唯一标识该关系模式中任何元组的属性组成
D.
以上都不是
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举一反三
【简答题】I'm sorry about that. I'll see to it at once. Can I , please?
【单选题】I'm sorry. I go now. My father told me on the phone that my mother was ill.
A.
can
B.
may
C.
have to
D.
need
【单选题】Flash 中要选取场景中所有层中的所有对象应执行下列操作 ( ) 。
A.
按住 Shift 键的同时进行选取
B.
执行“编辑→时间轴→选择所有帧”命令
C.
执行“视图→选择所有帧”命令
D.
在时间轴上点击帧
【单选题】Talia: I'm sorry. I know this will take some time, but I really think that you should rewrite this story.
A.
Alex: (Yeah, you may be right.)It isn't really very good.
B.
I see your point, I guess.
C.
Big deal!
【单选题】—I'm so sorry that I have broken your computer. 一 ________. I can mend it by myself. [ ]
A.
Never mind
B.
It's not good for you
C.
Bad luck
D.
OK
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