For instance, existing approaches classify text units as argumentative or non-argumentative (Moens et al., 2007), recognize argument components such as claims or premises at the sentence-level (Mochales-Palau and Moens, 2009;Kwon et al., 2007;Eckle-Kohler et al., 2015) or clause-level Sardianos et al., 2015), or identify argument structures by classifying pairs of argument components .
these approaches are of limited use for argumentative writing support systems since they do not recognize the weak points of arguments.