why is jack a round character?

A round character has many parts to their personality, just like you and me. Jack is a smart child but naïve because of his lack of exposure with worldly things. He counts, reads, and spells well and has a fairly extensive vocabulary. However, his speech patterns are not well developed because of his limited exposure to people and his lack of practice interacting with other people. When he escapes from Old Nick, he has trouble talking to the people who ultimately serve as his rescuers. Later, when he slips away from Grandma at a store, Jack talks to some other people and his Grandma is furious, knowing that something bad could have happened to Jack again. He is surprised to learn that there are other bad people in the world.