______ do you play football? —Once a week. [ ]
_____ it the TV?—It’s 2000 yuan.[ ]
The doctors did what they could_______ those w-ho were injured in the terrible accident.
Teenagers like reading the books ________ are written by Guo Jingming.
Look at ______ book on the desk . Is it ______ useful one ?—Yes, it is . In the book there is much advice on how to learn math well.