1. How many times does Minh brush his teeth a day?
2. What is problem after you eat that food?
3. When did Nga go to see a dentist?
4. Who will check your teeth?
5. How long did Dr. Phong take to fill Van's tooth?
6. Where is your brother going to?
7. What time did Mr. Cuong do morning exercises yesterday?
8. Whose letter did Hoa receive five days ago?
9. How many students in Lien's class having toothache?
10. Why is Nam in a lot of pain now?