M.A.K.Halliday is a grammarian who has tried to create a grammar which tried to include what I've been calling the 'social function' or 'functioning' of language.
For a while I've been asking around to see if anyone had worked on this grammar to create materials suitable for teachers, teaching and school students. A guy called Alan Hess has been in touch and here are his materials, that he devised which do just this:
http://manxman.ch/moodle2/course/view.php?id=4
