An Introduction to English Sentence Structure puts the study of English sentences into the meaningful perspective provided by the broad essentials of functionalism.
The book starts from the premise that the structure of language reflects the structure of events in everyday experience. By contrast, grammars that are more structural in nature often begin with gross facts about language structure, such as the observation that clauses can be divided into subjects and predicates.
The book's premise reflects the fundamental Hallidayan principle that language simultaneously codes for three dimensions of structure: clause as representation, clause as exchange, and clause as message. This approach has the effect of situating the study of language in the student's familiar world of ideas, relationships, and discourses.
The book blends insights from three prominent modern schools of grammatical thought (functionalism, structuralism, and generativism) using functionalism as the philosophical and organizational motif. The book focuses on the representational function of language, encouraging students to use their knowledge of the way the world works in order to understand how language works. The approach taken is hybrid: It assumes that form matters, and in this sense it is structural. It also assumes that form follows function, and in this sense it is functional.