根据内容、性质的不同，请示分为（）三种。
A.请求指示性请示
B.请求批准性请示
C.请示批转性请示
D.请求答复性请示
参考答案：A, B, C
-Listen! Is that Kate playing the piano in the room?
-No. It _____ be Kate. She has gone to London.[ ]
A. may not
B. needn't
C. mustn't
D. can't
