1. (2020八下·房县期末) 阅读短文，根据其内容，完成下列任务。

    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 let's learn to    ①   a computer safely.

    Your eyes. Too much light can injure your eyes. Your eyes should be more than 50cm from the screen. Don't forget to look away from it sometimes. This gives your eyes a rest.

    Your hands and wrists (手腕). Hand and wrist injures can happen because the hands and wrists are moved in the same way hundreds of times. If you use keyboard for a long time, follow these three rules:

A. Rest your wrists on something.

B. Keep your elbows (肘) as high as the keyboard.

C. Stop sometimes and exercise your hands, wrists and fingers in a different    ②   .

    Your back. Some people sit for many hours in front of a computer. If you sit in a wrong way, you can injure your back or your neck. So you shouldn't bend (弯下)your back when you sit. The top part of the sc reen 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, you should get up every half an hour and exercise your arms, legs and neck.

1. （1） 请根据短文内容，分别写出①、②处所缺的单词。（每空限填一词）

   ① ②

3. （2） 阅读短文，从短文中找出与下面句子意义相近的句子。

   Remember to take breaks away from the computer after a while.

5. （3） 请把文中划线的句子翻译成汉语。
7. （4） Why do hand and wrist injures happen?
9. （5） What shouldn't you do when you sit before a computer?