Kawabata 15. Krashen’s “monitor hypothesis” states that a subset of this process cannot produce its result spontaneously. It is examined in the wug test, and Kuniyoshi Sakai proposed that this process is represented differently in the cortex after its first occurrence. Piaget’s sensorimotor stage ends at its onset, and Lenneberg’s proposed critical period of it lasts until around age 5. Several “Forbidden Experiments” were conducted to study this in isolation. The Behaviorist view of this process expounded in Skinner’s Verbal Behaviorwas attacked by Chomsky, who holds that generative grammar better explains this and that children’s predilection toward it is innate. For 10 points, name this process of learning to use and understand a system including speech or writing.