1)Mike __ be home by now.His plane landed four hours ago.
a.must b. can't c.can d. mustn't
2)Henry __ come over today.He may finish work late.
a.couldn't b.didn't need to c.might not d. can't
3) I __ come to the concert tonight,but i'll give you a call later and tell you for sure.
a.may b.can c.must d.could
4) Ann __ be in her office right now. All the lights are off.
a.mustn't b.can't c.needn't d.doesn't have to