Computers can injure (伤害) you. Most other injuries happen suddenly. For example, if you fall over a bike and break your arms, it happens very     . But computer injuries happen slowly. You probably know how to ride a bike safely. Now learn to use a computer safely.

Your eyes      light can injure your eyes,       never sit too close to a computer screen. Your eyes should be       50centimeters（厘米）on the screen.       remember to look away from it. This gives your eyes a rest. When you use a computer, the window         be on your left or your right. If it is behind you, the light will reflect on（反射）the screen. If the window is in front of you, the sun and the screen will        shine into your eyes.

Your hands and wrists(手腕)

Hand and wrist injuries can happen because the hands and wrists are moved in the same way. Hundreds of times. If you use a keyboard for a long time,         these three rules: 1）Rest your wrists on some­thing. 2）Keep your elbows（肘）at the same height as the keyboard. 3）Stop sometimes and exercise your hands, wrists and fingers in a different way.

Your back

Some people sit for many hours in front of a computer. If you sit in the wrong way, you can injure your back or your neck. So you should sit with your back straight. The top part of the screen should be in front of your eyes. Your forearms, wrists, hands and the upper part of your legs should all be parallel（平行）to the floor. If you are sitting for a long time, get up every 30 minutes and        your arms, legs and neck.      your computer, but use it safely.

1.A. much quickly      B. faster                 C. slowly              D. quickly

2.A. Too many       B. Too much            C. Much too             D. Many more

3.A. so               B. because      C. but                   D. when

4.A. at last                   B. at most     C. at least         D. less than

5.A. Sometime  B. Some time         C. Some times     D. Sometimes

6.A. can            B. may                       C. must           D. should

7.A. both                B. never      C. all           D. neither

8.A. follow             B. work          C. copy              D. write   

9.A. need               B. exercise              C. walk           D. shake

10.A. Enjoy      B. Watch                C. Protect             D. Keep

If you often have a cold, headache or backache, there is something wrong with your health. Eating healthy food   43  good for our health. Tofu（豆腐）, milk, vegetables are healthy for us.
Tofu is a kind of traditional（传统的）   44  food. We often   45  it in China. Now more and more people   46  other countries think tofu is good for health,  47 . They also like eating it.
Milk is   48  kind of healthy food. Every day you should   49  one or two glasses of milk. It can   50  us strong.
Vegetables are very important. You should eat   51  them. There are vitamin(维他命) A, B, C, D , E and so on in them.
As we know, it’s important   52  a balanced diet(均衡饮食). We must have the right kinds of food. We should also eat some pork, chicken and beef. We should eat more fruit and vegetables but less meat.

Every time you turn on the television or take a ride in a car ,you could be adding to a problem called acid rain(酸雨). In this article, you’ll learn how acid is created, and how it affects us, and more importantly, what we all can do to prevent it.
How is acid rain created?
When people use fuels(燃料), such as coal and gasoline, poisonous gases are give off. When these gases mix with rain, acid rain forms. Many power stations burn fuels in order to creat the electricity(电) that we use in our homes and offices every day. Cars and trucks also send these gases into the air when they burn gasoline .When rain mixes with these gases, harmful things called acids form. This is acid rain.
How does acid rain affect us?
Acid rain damages(毁坏)everything that it touches. It poisons our rivers, ponds, lakes, and oceans along with all the life in them. It pollutes our soil and crops, harms trees, and can even kill fish and plants. Acid rain also eats away at buildings.
How can we prevent acid rain?
We need to cut down on the pollution that gets into our air. Turn off lights, television, and other electrical appliances if you are not using them, Walk or take a bike whenever possible. If you are travelling a long distance, take a bus or train to save fuel.
As research shows, acid rain harms our environment. But people everywhere can take small steps now to help protect our environment for future generations.
【小题1】When power stations burn fuel,_______.

阅读下面短文，完成表各中所缺信息，每空一词

What if there is a fire in your house? Would you know what to do? Here are several suggestions which might help you escape (逃生) from the fire.

Leaving the house through a door should be your first choice as an escape route. Windows on a higher floor may be a safe escape route if you could get help from another person.

     If you can see smoke in the house, stay low to the ground as you go to the door. In a fire, smoke and poisonous air hurt more people. You’ll breathe less smoke if you stay close to the ground.

If fire or smoke is blocking (阻塞) an escape route, you do this, firefighters (消防队员) will have difficulty finding you. The sooner they find you, the sooner you can get out.

Meanwhile, keep heat and smoke from getting through the door by blocking the cracks (缝隙) around the door with blankets, or clothing. If there is a window, open it all the way and stand in front of it. If you can get a piece of clothing, cover your mouth to keep from breathing in the smoke. This works even better if you wet the cloth first.

If your clothed catch fire during a fire, don’t run! You had better stop, drop to the ground, and roll. This will cut off the air and put out the fire.

If you often have a cold, headache or backache, there is something wrong with your health. Eating healthy food 1  good for our health .Tofu（豆腐）, milk, vegetables are healthy for us.
Tofu is a kind of traditional（传统的）   2  food. We often   3  it in China. Now more and more people   4  other countries think tofu is good for health,  5 . They also like eating it.
Milk is   6  kind of health food. Every day you should   7  one or two glasses of milk. It can   8  us strong.
Vegetables are very important. You should eat   9  them. There are vitamin(维他命) A, B, C, D , E and so on in them.
As we know, it’s important   10  a balanced diet(均衡饮食). We must have the right kinds of food. We should also eat some pork, chicken and beef. We should eat more fruit and vegetables but less meat.