We live in the computer age. People use computers to do much of their work. But few people know how to look after them. Remember the following when you use your computer:
    ① 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.
    ② Do not let people smoke near your computer. Smoke of all kinds is very bad for many parts of a computer.
    ③ Do not eat or drink when you are near your computer. Pieces of food and a little water in the keyboard are also bad for a computer.

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