1.Chọn và điền các từ dưới đây vào hội thoại: “cause;decay;eat;middle- aged;pulled;sugar;teeth;thought;treat;wear." Many people nowadays have to_________false teeth when they are_________. The reason is that tooth________increases a lot. The sugar is chief________of tooth decay. Eskimos'_________, for example, when they began to________sweeter food. Long ago doctors didn't like to________people's teeth. People's teeth and_________them out when they decayed. Some people_________toothache was a punishment from the gods.

What does the doctor recommend to eat?

What do happy people do? 

What kind of food will help people to keep fit and stay healthy?