---- _______?-----A bag.
—Is this ______ model plane?—No, it isn’t ______.
—Who’s that at the door?—_____ is John.
如果你向玛丽介绍自己,你应该说:_______
— Your bag looks heavy. Do you need a hand?— . Thanks all the same.
---What are you going to do this weekend?----- I _____ yet.