This document provides an overview of Mehdi Taghavi's presentation on first language acquisition. It discusses the areas of study in language acquisition, including descriptive data, stages of language development, and how acquisition data can be used to test theories of grammar and develop a theory of acquisition. It also compares the perspectives of child language versus language acquisition between psychology and linguistics. Key points discussed include the distinction between a theory of language and a theory of acquisition, principles that govern morphology and syntax development, and assumptions about the relationship between a child's developing grammar and the adult grammar.