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Functions of discourse markers

marker

comment

ah well

marks a shift to a ‘dispreferred’ or divergent next utterance: the professor

diverges from the student’s line of argument

so 

(

3)

mark conclusions reached by the student

good 

(

2)

mark the professor’s satisfaction with the direction of the discussion

well

marks the professor interrupting or pre-empting the student’s conclusion in

order to present his own conclusion

yeah

marks the professor’s assumption that the student will concur with his view of

the situation

okay

marks the professor’s desire (and power) to end the conversation