Dale is seven. He can go to school. On the first day, his teacher teaches him three words "I, you, he". The teacher says, "I am your teacher. You are my student. He is your classmate, "After class, Dale goes home. His mother asks him, "What does your teacher teach you today?" Dale says, "Listen, mom, I am your teacher. You are my student." He points at(指着) his father and says, "He is your classmate." His mother says, "No, dear. You are not right." Then she says, "I am your mother. You are my son. He is your father. "The next day, Dale's teacher asks Dale to make sentences. Dale stands up and says, "I am your mother. You are my son. He is your father." All the students in Dale's classlaugh.