题目内容：

Everyone wants to have healthy teeth. When you laugh, you will____your mouth and show your teeth. The healthier your teeth are, the happier you feel. Why is that?

It's____your teeth are important in many ways. Take care of them, and they'll help to take care of you. Strong,____teeth help you grow. They also help you speak clearly. You can take care of your teeth by doing like these:

Brush your teeth____a day, after getting up and before bedtime. And you brush all of your teeth, not just the front ones. Spend some time____the teeth along the sides and in the back. Take your time while brushing. Spend at____three minutes each time you brush. Be sure your toothbrush is soft. Ask your parents to help you get a new toothbrush____three months. Clean between your teeth with dental floss(牙线). It feels strange when you do it at first, but soon you'll get used to____it. Brushing____your teeth healthy. You also need to care about what you eat and drink. Eat____fruits and vegetables and drink water instead of drinks.

Do you want to have white and healthy teeth? Please brush your teeth!

1.A. close    B. wash    C. serve    D. open

2.A. though    B. because    C. if    D. when

3.A. tight    B. white    C. healthy    D. clean

4.A. once    B. twice    C. three times    D. four times

5.A. on    B. in    C. at    D. to

6.A. first    B. least    C. once    D. last

7.A. every    B. both    C. either    D. neither

8.A. helping    B. making    C. feeling    D. doing

9.A. starts    B. produces    C. keeps    D. suggests

10.A. a lot    B. lots of    C. few    D. a little