Book excerpt: This Language, A River is an introduction to the history of English that recognizes multiple varieties of the language in both current and historical contexts. Developed over years of undergraduate teaching, the book helps students both to grasp traditional histories of English and to extend and complicate those histories. Exercises throughout provide opportunities for puzzling out concepts, committing terms and data to memory, and applying ideas. A comprehensive glossary and up-to-date bibliographies help to guide further study.