By now, your dog is 11 months old. The best course of action is obedience training. "Mouthing" and "nibbling" are different from "chewing."

Mouthing dogs will very gently take your arm or hand between their teeth, sometimes as a natural form of "domination." In nature, only the most dominant dogs get to eat. That is the inherent pack mentality that all dogs share from their lupine ancestors.

The cure: take your body parts out of the dog's mouth and, using two fingers, tap with increasing vigor on the dog's nose, but do not get rough with this technique: it can be quite painful to the dog and they will react unpredictably or even fearfully.

"Nibbling" behaviors go a little farther than "mouthing." In this case, the dog means business and may not let go without you firmly saying, "No! Bad dog!" Professional dog training may be the best option.

"Chewing" is another "dominance" trait: if you value it, the dog will assert dominance over you by chewing it to shreds and then let you find it. He will smile only as long as YOU submit to HIS dominance.

Again, you have a potentially dangerous situation that can lead to resource guarding and other, more aggressive displays.

In any case, YOU must be the leader of your pack. Be firm, be kind, but make sure that your dog knows that you are the Alpha Member, yoiu are onto his games, and you will put him in the back of the pack the next time he fails to heed your leadership.