This document outlines various linguistic theories and approaches to the study of language. It discusses the aims of linguistic theorizing as explaining underlying principles of how language works through observation and generalization. Some key approaches covered include Saussure's structuralism which viewed language as a system of signs, Chomsky's generative grammar which aimed to model speakers' innate linguistic knowledge, and cognitive approaches like prototype theory and conceptual metaphor theory that view linguistic structures as reflecting mental representations of the world. The document also outlines American structuralism, semantic roles in Fillmore's case grammar, and psycholinguistic approaches focused on language acquisition and processing.