Hi,
What is discourse grammar?
Discourse means conversation.
The traditional approach to grammar tends to look at just single sentences, in isolation. My understanding of discourse grammar is, simply put, that it involves looking at complete conversations or communications between people, and even at the social context that these exchanges occur in. You might say it involves looking at the way people actually talk to each other.
The term that I am more familiar with is 'discourse analysis'.
Best wishes, Clive