When we have small cuts in the skin(皮肤), something strange may happen. The cuts are able to heal(痊愈) themselves in a couple of days. How does this happen? Read on, and you will find out the secret.
Every living thing on the earth is made up of cells(细胞). Cells grow and make new cells. Most cells are very small and we can't see them with our eyes. Different cells have different uses. Our skin cells are special ones. The cells on the outside of our skin are old dead cells. New skin cells are right under the outside. These are the living skin cells. They work for our bodies. They help protect our bodies and heal cuts.
Our bodies make skin cells all the time. As the old cells fall off, new cells grow in the same place. Each person makes about 18 kg of skin cells during his or her life. Outside skin cells fit together closely with no gaps between them. When you cut yourself, you can harm your skin cells. A small cut will not be harmful. Your skin will quickly heal itself by making new skin cells. How do skin cells work? First, the cells near the cut get bigger and move into the gap. Next, these bigger cells meet in the middle. They form a new layer(层) of skin cells. Finally, new cells will grow until the gap disappears. In this way, your skin can grow and get well itself. How amazing the small cells are! Next time you have a cut, don't worry about it. Maybe in a few days, you will be surprised to find it healed.
【小题1】The underlined word “gaps” in the passage means “______” in Chinese.

请阅读下面短文，掌握其意思，然后从方框中所给方的词中选出最恰当的10个，用适当形式填空。（每小题1分，共10分）

In America, science is a very important class. In middle school we were __1._ how to solve problems by thinking like a ___2.__. We had to think of a question, guess an answer, and ___3.__ a way to test our guess. There were lots of experiments and other activities. I remember studying how science can explain things like light and electricity.

Our English class is very different from___4.__ in China, more like Chinese class I think! We read lots of books and talked about them, ___5._ we could understand what we read better. We learned how to know what information is important when we read and what ___6._ so important. In my class we all gave six ___7._ to the class during the year. We had to talk in front of the class for six __8.ten minutes!

We also have health classes. In this class, we learned about our bodies and how to take care of ___9.__ by doing things like eating healthy foods, and not doing ___10.__ things like smoking or drugs (毒品). We cooked a little bit, but I was not very good at it!

Everyone likes living in a clean and comfortable environment. If the envionment(环境) is bad, it will affect（影响）our bodies, and make us not feel well. Sometimes we may be terribly ill. At that time we don’t want to work, and we have to stay in bed and rest at home. So the envrionment is very important to us.
It’s germ that makes us ill. There are germs everywhere, They are very small and you can’t find them with your own eyes, but you can see them with a microscope（显微镜）. They are very small and there may be hundreds of them on a very small thing, Germs can always be found in the dirty water. When we look at dirty water under the microscope, we shall see them in it. Germs can also be found in air and dust（灰尘）. If you cut your finger, some of the dust from the floor may go into it, and you will have much pain in it. Sometimes the germs will go into all of your boby, and you will have pain everywhere.
To keep us healthy, we should try to our best to make our environment become cleaner and tidier. This needs us to act together.
【小题1】The writer tell us that________.

During the day we work and play, and at night we sleep. Our bodies rest while we are   1 . In the morning we are ready  2  again. Our bodies grow   3  while we are asleep. Children who are tired usually   4  sleep. We can get better at our lessons  5  we have had plenty of rest. Boys and girls who are eight or nine years old need ten  6 sleep every night. Our bodies need plenty of   7  when we sleep. If we do not get enough fresh air, we      8  tired when we wake up. While in bed we must not cover our   9 . Our lungs(肺) needs to get  10 fresh air. If we   11 our windows at night, we can have plenty of fresh air. Cool air is better than warm air. Boys and girls who want to be   12  must get plenty of sleep.

Also, we need some after-school activities to keep in good health.   13 _students run every day. Some boys play basketball  14 a week.   15  girls,  some  often  play volleyball….So good sleep and exercise can help us grow better and study better.

1.                A．asleep         B．sleep           C．rest  D．play

2.                A．to work and play  B．working and to play   C．to work and playing  D．working and playing

3.                A．much          B．more           C．most D．slow

4.                A．can            B．may            C．need D．must

5.                A．while          B．before         C．as   D．after

6.                A．hour           B．hours          C．hour’s  D．hours’

7.                A．air             B．sun            C．water    D．food

8.                A．felt            B．will feel         C．are feeling D．has felt

9.                A．foot           B．arm            C．head D．body

10.               A．many          B．much          C．lots of D．enough

11.               A．open          B．close          C．draw D．use

12.               A．happy          B．interested      C．helpful    D．healthy

13.               A．much          B．more          C．many D．a lot

14.               A．one or two times B．one and two times C．once or twice   D．once and twice

15.               A．So            B．But            C．And  D．As for