—Is that Mr Li under the tree? —No, it _
题型:选择题
问题:
—Is that Mr Li under the tree?
—No, it ______ be him. He's in the office now. [ ]
A. can't
B. mustn't
C. might
D. must
—Is that Mr Li under the tree?
—No, it ______ be him. He's in the office now. [ ]
A. can't
B. mustn't
C. might
D. must