Why do dogs chew us?

I have a dog --puppy new at lest the people I live with also live with a dog. Actually its still a puppy. Now puppies pose real problems for those of us of a plushie persuasion. First of all little doggies CHEW! And (worse) they chew soft stuff -- like slippers and me!!!!!!
My (their) dog is cute --OK! And he's not very smelly... but he has tried chewing me and I fear he might try it again ... has anyone got any advice on how to stop me being chewed to DEATH?
Thansk
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