—Must I take much medicine every day?—No, you ________.

–Look at that girl! Is it Susan? --No, it _______ be her. She went to her hometown just now.

We'd better wait     more minutes. I think Jeff will come soon,

--Is the man standing outside the teacher’s office Mr. Zhou?  --No, it ______ be him. He has gone to Hong Kong for an academic conference. 

— _    good time we had at the party last night!— Yes. It was _____ exciting party that I would never forget it.