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【单选题】
设有关系R和S如下图所示,通过关系运算R÷S的结果是( ) R: X Y S: Y F X1 Y1 Y1 F1 X2 Y2 Y2 F2 X2 Y3 X2 Y1A.
X1
B.
X2
C.
X1，Y1
D.
X1，X2
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皮皮学刷刷变学霸
举一反三
【单选题】——Must I stay here now? No, you ______ . ——You go home now.
A.
mustn't, may
B.
can't, can
C.
needn't, may
【多选题】贸易全球化是指商品和劳务在全球范围内自由流动。衡量贸易全球化的指标包括
A.
全球商品贸易增长速度加快，贸易规模越来越大，服务贸易、技术贸易、产业内贸易、跨国公司内部的贸易在全球贸易中的比重不断上升。
B.
参与贸易的国家急剧增加，对外贸易在各国国民经济中的地位和作用进一步提高，成为许多国家经济增长的 “引擎”和最重要的增长源。
C.
国际贸易体制和规则更为规范，对全球贸易活动进行规制和调节的范围和作用趋于扩大。
D.
更为便捷的通信和运输条件和日益先进的贸易手段的使用，推动着贸易全球化。
E.
各国政府采取了更为开放的贸易政策。
【单选题】Henny _________ be at home now because he phoned me from the school just now . [ ]
A.
mustn't
B.
isn't he able to
C.
may not
D.
can't
【单选题】Are they on the playground now?
A.
Yes, they are.
B.
No, they aren't.
C.
They were, and now they are back.
【单选题】Which of the italicized parts functions as a subject?
A.
It seems unlikely she will refuse the offer.
B.
She took for granted that her son would study medicine.
C.
The odds are that he will not do it.
D.
Stories that the house was haunted angered the owner.
【简答题】1t is afternoon now．30．1t is afternoon now．
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