—Who _____ it be that is knocking at the door?
—It ______be father, but I’m not sure.
A. can; may B. may; can C. may; must D. need; should
—Who _____ it be that is knocking at the door?
—It ______be father, but I’m not sure.
A. can; may B. may; can C. may; must D. need; should
A