Boy, that looks awful doesn't it? Two puppies biting and scratching and chewing and beating the tar out of each other! Well, let me tell you, it's FUN!! (most of the time). By the way, we weren't REALLY fighting - we were just playing.
Some puppies know that when you play, you should NOT really try to hurt each other. Those are the good puppies. Some puppies haven't learned to play nicely yet. The tall guy says I must have had a good mother and father, because I try to play nicely with all the puppies - even the ones who haven't learned good manners yet!