The rhetorical structure will comprise just two propositions linked by a concession relation: concession(ban(fda, elixir), approve(fda, elixirplus)) The method works by computing the options for realizing each constituent of the rhetorical structure, where a constituent is any node in the rhetorical structure tree along with its descendents.
in the present example there are three constituentsthe two propositions and the whole relationship-and for convenience we will label them as follows: A: approve(fda, elixirplus) B: ban(fda, elixir) C: concession(ban(fda, elixir), approve(fda, elixirplus)) We can now begin to characterize the units in the document structure that will realize the rhetorical constituents A, B, and C. For each unit, four choices must be made: its level, its indentation, its position in relation to its sisters, and its connective.