Computers can injure you. Most other injuries happen suddenly. For example, if you fall off a bike and break your arms, it happens very fast. But computer injuries happen slowly. You probably know how to ride a bike safely. 【小题1】

Your eyes

Never sit too close to a computer screen. Too much light can injure your eyes. Your eyes should be at least 50 centimetres from the screen. After some time, remember to look away from it. This gives your eyes a rest. 【小题2】 If it is behind you, the light will reflect 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. 【小题3】 First, rest your wrists on something. Second, keep your elbows at the same height as the keyboard. Third, 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. 【小题4】 Your forearms, wrists, hands and the upper part of your legs should all be parallel to the floor. If you are sitting for a long time, get up every 30 minutes and exercise your arms, legs and neck.

【小题5】