皮皮学，免费搜题
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【单选题】
下列哪些语句对主键的说明正确 ( )A.
主键可重复
B.
主键不唯一
C.
在数据表中的唯一索引
D.
主键用 foreign key
拍照语音搜题，微信中搜索"皮皮学"使用
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皮皮学刷刷变学霸
举一反三
【简答题】Last year Mike earned ________ his brother, though his brother has a better position. A) twice as much as B) twice as many as C) twice than D) twice as more as
【单选题】He has heard from his elder brother.
A.
has received his elder brother’s letter
B.
has heard of the news of his elder brother
C.
has bought a gift for his elder brother
【简答题】阅读理解。 Jack is six years old. He has no sisters. But he has a brother. His brother's name is Mike. Jack likes eating apples, oranges and bananas. Sometimes he eats some of his brother's apples. And his...
【单选题】He has a brother .(改一般疑问句)
A.
Has he a brother?
B.
Is he has a brother?
C.
Does he have a brother?
【单选题】Helen has two sisters and a brother. Her brother is working, but _________her sisters are still at school.
A.
neither
B.
either
C.
all
D.
both
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