Spoken grammar has some similarities to the Standard English grammar used in writing, but according to Prof Ron Carter, spoken grammar is characterised by some of the following features:
HEADS (starting with the most important idea or subject) e.g.' the girl in the white coat, is she the one we saw earlier?'
TAILS (subject at the tail end for emphasis) e.g. 'They're messy to peel, aren't they, oranges?' ELLIPSIS (missing words that are likely to be implied) e.g. 'Sounds good to me.'
DISCOURSE MARKERS (words signalling a change) e.g. 'Right, we'd better go.'
Other features include vague language using words like whatever, stuff and things and phrases such as 'sort of'.
There is much more to the grammar of talk than these few headings, but children become fascinated if you allow them to record themselves having a short conversation and then let them analyse it and compare it to the grammar used in writing. A fascination with language is surely what we want to encourage in schools as it has all sorts of spin offs. Asking children to look out for Heads, Tails and Discourse Markers is a start and fun to do.