问题补充：
— Who’s singing in the next room?
— It be Mary. She New York.
A. mustn’t, is in
B. must, has gone to
C. could, has been in
D. can’t, has gone to
答案：
A. mustn’t, is in
B. must, has gone to
C. could, has been in
(答案→)D. can’t, has gone to
解析：
试题分析: 句意:谁在隔壁唱歌呢？不可能是玛丽，她已经去了纽约了。Mustn’t千万不要，must肯定，could可能，can’t不可能。is in在，has gone to已经去了某地还没回来，has been in已经在某地。根据语境可知是在此处的不可能是玛丽，因为她已经去了纽约了，故答案选D.
