Purpose: Keep your puppy away from accident, train him not to eat the food given by strangers.

Command: "No". When your puppy is going to eat the stranger's food, say "No" to him loudly, at the same time, pull the leash with force to stop him, so that the puppy may establish conditioned reflex to the conmmand. Certainly, you must train your puppy frequently at other times, in this way, he can remember that forever.

Participator: The owner and a assistant as stranger. Take your puppy to a quiet place, the assistant approach the puppy naturally, and give him food. If the puppy eat it, strike his mouth. Give food again, if the puppy still eat, beat him strongly. At the same time, say "No" to your puppy, pretend to strike the assistant, which can excitated the puppy's active defense reaction. When the puppy barks at the assistant, assistant should run away at once. After this, the puppy should be awarded by owner. Train the puppy again and again until conditioned reflex is established.

Another method: Ask one of your friends for help, he/she must not be familiar with the puppy. Feed the puppy the food mixed with something acid or bitter, repeat every two or three days, as far as he refuses foods from any strangers.