In recent studies, various classes of features are explored to capture lexical and semantic regularities for identifying the sense of implicit relations, including linguistically informed features like polarity tags, Levin verb classes, length of verb phrases, language model based features, contextual features, constituent parse features and dependency parse features <cite>(Lin et al., 2009</cite>; Pitler et al., 2009; Zhou et al., 2010; Zhang et al., 2015; Chen et al., 2016) .