--Listen! Someone is knocking at the door. Who _____it be?---It_____be Tom. He phoned to visit me this evening.

“Mary looks hot and dry.” “So _____ you if you had so high a fever.”

—Look at the young lady in red. Is it Mrs. King?—No, It ________ be her. She is wearing a white dress today.

She _____ your birthday party, but she had to look after her mother in hospital．

“No student,” the headteacher stressed, “_______ go out of the school after ten o’clock at night without my permission.”