Examines the development of children's understanding of the difference between "want" and "need" in two different experiments. The first experiment required the children to respond verbally in choosing between the two concepts; the second required them to give an object to one of two characters who had made a request using…

A study of overregularized use of verbs by two children over a period when they were 2 1/2 to 5 years of age shows overregularizations in two directions: non-causative verbs were used as causatives; and causative verbs were used non-causatively. According to terminology from logic, predicates were classified according to the number of noun-phrase…