---Mum, have you seen my U-Disk?---____________ you bought last Sunday? I'm afraid I haven't seen ________.
What do you think ______ an apple ______ to the ground?
Why do you think ______ cut down the big tree?
—— ______ if I smoked? ——I'm sorry, but it's not allowed.
Do you think his tie is _________?
Mary said that she ___________ London.