—Jack is not in the office at the moment—Oh, he ______ those who are going to take the driving test in an hour.

－These peaches really juicy.－They ____ be! Just see the price, $3,99 a pound. Very expensive, aren’t they!

(2013·湖南高考)He ________ sleep, although he tried to, when he got on such a hunt for an idea until he had caught it.

— I am going to the dentist at 4 o'clock and it is 3：30 now.— Well, if you ______ leave earlier today, please ask the director for permission.

—Someone is knocking at the door. Is it Ann?—It _____ be her. She is giving a performance at the theatre now.