Imagine standing at an IPO Schutzhund trial with your beautiful, strong German Shepherd. He is all grown up now. You command "Achtung!" and he snaps to attention. You command "Sitz", then "Bleib". A man covered with padding appears on the field, and you command "Fass!". Your dog takes off and grabs the man by the arm, holding him there with a controlled bite. You command "Aus!" and your dog releases his hold on the man.
You have just told your dog to pay attention, sit, stay, and grab onto the padded person. You then told your dog to let go, and your dog obeyed wonderfully. Today was a successful IPO trial for both you and your dog.
It might be hard to picture your little bundle of fur doing all that right now. He certainly mouths you, with tiny needle-sharp teeth, but he is completely goofy when he does it and hasn't learned how to do anything on command yet. He is all wiggles, fluff, and play right now. Which is how a young puppy should be, but underneath that adorable fluff is also a pup who desires to please you, to learn, to work, and to be stimulated. Your guy can go far with your help, and he can go far in German also!