The document discusses the stages of language development in children. It describes Chomsky's Language Acquisition Device hypothesis and Skinner's behaviorist view of language learning. The stages include the prelinguistic period where children engage in babbling and gesturing, the holophrastic period marked by one-word utterances, the telegraphic period when two-word combinations emerge in the form of agent-action or action-object relations, and finally the complex period where children start using grammatical morphemes and forming basic sentences.