There ____ a stamp collection show in the museum this afternoon.
It’s _____ hard problem for the twins that ____ of them can work it out.
You ______ to the party if you’re so busy.
—_____I use your dictionary, Tom? —Of course, you _______
Simon improved his way of study. ________, he has made great progress.
—What colour is _______ orange ? —It's____ orange .