.--- Who would you like ______ to the ball with? ---Of course Mary. We’ll start at 6:30 and try to get there before 7:00.
The research is so designed that once ____ nothing can be done to change it.
______ in thought, he almost ran into the car in front of him.
Not only ____ the jewelry she ____ been sold for her son's gambling debts but also her house.
The man whose songs we are fond of ____ in our city next week.
The person we talked about ____ our school last week.