从字符串S("abcdefg") 中返回子串B("cd") 的正确表达式是______。

A．Mid(S,3,2)

B．Right(Left(S,4) ,2)

C．Left(Right(S,5) ,2)

D．以上都可以

小医生，下列各句均有一处错误，请找出并改正。

1.Which year was your brother born?

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2.Do you like to look English stories?

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3.My birthday is in July 25th.

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4.I like action movies and I don't like comedies.

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5.Aunt Li has two babys.

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