题目内容
David can't go with us now because he __________ the school project.
A.does B.has done C.did D.is doing
快捷英语周周练系列答案We all know teeth are important to us, and we have National Teeth-Loving Day on September 20 th every year. Do you know the life cycle of teeth in your mouth? Children under 6 years old have 20 baby teeth. From 6 to 13, people lose their baby teeth one by one. Now permanent teeth（恒牙）begin to grow. Between the ages of 17 and 25, some people grow wisdom teeth（智齿）. Of course, wisdom teeth don't make you any smarter. They look like a symbol（象征）of being grown-ups（成年人）.
Do you know how to keep our teeth strong and healthy? Let's look at the following tips.
What we can do:
Brush your teeth in the morning and before bedtime.
Brush for at least two or three minutes every time.
Brush up and down on every tooth.
Use a dental floss（牙线）for your teeth to make them cleaner.
Get a new toothbrush every three months.
What we can't do:
Don't eat too much sweet food, like candy and ice cream, or don't drink too much soda.
Don't eat very hard food. That can hurt your teeth.
Don't eat snacks before bedtime.
It's clear that healthy teeth help us eat food to let us grow. They help us speak clearly. And yes, they help us look good.
Title: Teeth are 1. to everyone. | ||
The 2.of National Teeth-Loving Day | It's on September 20th every year. | |
The life cycle of teeth | Children under six have 20 3. teeth. From 6 to 13, permanent teeth begin to grow. Between 17 and 25, some people grow wisdom teeth that mean they are not 4. any longer. | |
The 5. for keeping teeth strong and healthy | Things we can do | Brush your teeth at least 6. a day: in the morning and before going to7.. Brush for 2-3 minutes every time. Brush up and down on all the teeth. Use a dental floss to make your teeth cleaner. 8.your toothbrush every three months. |
Things we can't do | Never eat too much 9. food or drink too much soda. Don't eat very hard food because that can hurt your teeth. No snacks before going to bed. | |
The importance of teeth | It’s10. to have healthy teeth when we eat food to grow, and they can also help us speak clearly and look good. |
