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This is ______ interesting story-book and it is also ______ useful one.
A. a;a B. an;an C. an;a D. a;an
从所给的四个选项中选择最佳答案
This is ________ interesting story-book and it is also ________ useful one.
[ ]
A．a ... a B．an ...an
C．an ... a D．a ... an