Isaac is concerned to establish that objects in books exist in the real world.  For example, he points to a picture of a clock in one of his books, says 'clock', then points to the clock on his wall, and says 'clock' again.  He does the same at Dylan's nursery, where there is both a clock and a book depicting a clock.  He also points to a door in a book and the door in his room, saying 'door' each time.

Isaac says, with some difficulty, 'star' (har), 'apple' (ah-uh), 'banana' (nana), 'orange' (oh-ah), and 'flower' (fla).  He also says bubble, hair, hat, spoon, fork, chair, keys, teddy, ball, boat, pear, carrot, baby, cake, milk, tree, sheep, top, balloon, and man.