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    Germs are always in dirty water. When you look at dirty water under a microscope, you will see them in it. So your parents will not let you drink dirty water.

    Germs are found not only in dirty water, they are also found in air and dust. If you cut your finger, and if some of the dust goes into the finger, it will become big and red, and you will have much pain in it. Sometimes they will go into your body and you will have pain everywhere.