题目内容：

Computers can injure you. Most other injuries happen suddenly. For example, if you fall off a bike and break your arms, it happens very quickly. But computer injuries happen slowly.

You probably know how to ride a bike safely. Now learn to use a computer safely.

Your eyes

Too much light can injure your eyes, so never sit too close to a computer screen. Your eyes should be at least 50cm from the screen. Remember to look away from it sometimes. This gives your eyes a rest.

When you use a computer, the window should be on your left or your right. If it is behind you, the light will reflect(反射) on the screen. If the window is in front of you, the sun and the screen will both 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, follow these rules: ①Rest your wrists on something. ②Keep your elbows at the same height as the keyboard. ③Stop 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 the parallel (平行) to the floor. If you are sitting for a long time, get up every 30 minutes and exercise your arms, legs and neck.

1.A computer screen may injure your eyes if __________.

A. you sit 60cm away

B. your eyes are too close to it

C. the window is on your left or right

2.Hand and wrist injuries are caused when you __________.

A. move in the same way again and again

B. rest your wrists on something

C. keep your elbows as high as the keyboard

3.When using a computer, your eyes and hands will be safe if you __________.

A. work near a window

B. work for a long time

C. take rests at times

4.It is good for your back and neck if you sit __________.

A. for many hours

B. in the right way

C. with the screen below your eyes

5.What would be the best title for the text?

A. How to Use a Computer Safely

B. How to Keep your Hands and Wrists Safe

C. How to Protect your Eyes and your Back