Many young people can use a computer, but few of them know how to look after it. Remember the
following tips when you use a computer.
         Keep your computer in a cool, dry room. Too much or too little heat is bad for computers. Damp (潮湿)
is also bad for them. Most computers work best at a temperature of 5-10 degrees centigrade (摄氏度).
         Do not let people smoke cigarettes near your computer. Smoke of all kinds is very bad for many parts of
the computer and can cause many problems.
         Do not eat or drink when you are near your computer. Pieces of food or drops of water on the keyboard
can also cause many problems.
         Make sure that the keyboard and the screen are the correct height for you. If they are not correct, you
will get backache.
         Make sure the screen is the correct distance from your eyes. If you wear glasses, make sure these glasses
are correct for using with the computer. Some people use a different pair of glasses when they use a computer.
         Keep your screen clean and do not have it too bright. A dirty screen can hurt your eyes. A very bright
screen can also be bad for your eyes. If you can afford one, buy a computer screen. It will be better for you
than using the screen of a TV set.
         Never use any software (软件) that you don't know whether they are clean or not. You must be careful
because some software can bring viruses (病毒) into the computer. If your computer has viruses, it can't work
or even breaks down.

(     ) 1. According to this passage, most young people can control computers well while paying little attention
            to the keeping of them.
(      ) 2. Putting the keyboard and the screen too high means you don't have to look at your manuscript (手稿)
             while typing.
(      ) 3. Some people use a different pair of glasses when they use a computer because they want to protect
             their eyes.
(      ) 4. It's better to use a TV set screen instead of a computer one because a TV set is usually larger than a
             computer one.
(      ) 5. "Clean software" means the software without any viruses.