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搜题
【单选题】
What did Juan ask his roommate to do when he was making his trial speech?A.
Interrupt him whenever he detected a mistake.
B.
Focus on the accuracy of the language he used.
C.
Stop him when he had difficulty understanding.
D.
Write down any points where he could improve.
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举一反三
【单选题】—Have youever been to Singapore ? — Yes, I ____ there last year with my parents.
A.
go
B.
went
C.
have been
D.
was going
【单选题】关于债的法律关系，正确的表述是
A.
债权人是特定的，债务人是不特定的
B.
债务人是特定的，债权人是不特定的
C.
债权人和债务人都是特定的
D.
债权人和债务人都是不特定的
【简答题】______ 是数据的基本单位,有些情况下也称为元素、结点、顶点、记录等。