An Introduction to Functional Grammar, 3 edition

In this extensively revised third edition, Halliday and Matthiessen retain the organization and topical coverage of the earlier editions, while incorporating a considerable amount of new material. They give greater emphasis to the systemic perspective, in which grammaticalization is understood in the context of an overall model of language. Their description of grammar is grounded in a comprehensive theory, but it is a theory which evolves in the process of being applied.