If you want to change for a red one you'll have to pay ___________ $ 20.
Time should be made good use of ____ our lessons well.
---What do you think made the woman so upset? --- _____ weight.
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.