----Who______ it be that is knocking at the door?
----It ______ be Father, but I’m not sure.
A. can; must B. must; can C. can; may D. may; must
----Who______ it be that is knocking at the door?
----It ______ be Father, but I’m not sure.
A. can; must B. must; can C. can; may D. may; must
C