... aspect is still expressed derivationally ; for a good descrip- tion of the Hittite system see Hoffner and Melchert 2008 : 317-23 . The PIE system was based on an opposition between perfective and imperfective stems ; apparently most ... This book describes the earliest reconstructable stages of the prehistory of English, focusing specifically on linguistic structure. It outlines the grammar of Proto-Indo-European, considers the changes by which one dialect of that prehistoric language developed into Proto-Germanic, and provides a detailed account of the grammar of Proto-Germanic. In the course of his exposition Don Ringe draws on a long tradition of work on many languages, including Hittite, Sanskrit, Greek, Latin, Slavic, Gothic, and Old Norse. This second edition has been significantly revised to provide a more in-depth account of Proto-Indo-European, with further exploration of disputed points; it has also been updated to include new developments in the field, particularly in the reconstruction of the Proto-Indo-Europe