—I can't find Mary. Where's she? —Sorry,
问题:
—I can't find Mary. Where's she?
—Sorry, I don't know ______. [ ]
A. where has she been
B. where she has been
C. where has she gone
D. where she has gone
—I can't find Mary. Where's she?
—Sorry, I don't know ______. [ ]
A. where has she been
B. where she has been
C. where has she gone
D. where she has gone