--- Look! It ____ be Jack on the playground.---It ____ be him. Because I saw him enter the school library just now.A. may; mustn’t B. must; can’t C. can; can’t
—Why didn’t Jim go to the movies? —He was made out of the hall for making lots of________.
They both have________homework to do,so they may be________busy doing it now.
—What are you doing,Mike? —I’m waiting for the________of the wallet that I found on the road.
A strange thing happened________her last night,so she is afraid to stay at home alone tonight.
—Mike,do you know which CDs belong to________? —I’ve no idea.You may ask Alice.