- Tom, where is your father?- I’m not sure. He _______ in his office.
#74723
A
must be
B
may be 
C
maybe
D
need be
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-Hello, _______ I speak to Lily? -Hold on, please.
#74494
A
may
B
must
C
need
D
should
Last night Li Ping watched the football match at my home, so he________ in his office. 
#63219
A
needn’t have worked
B
mustn’t haven’t worked
C
shouldn’t have worked
D
couldn’t have worked