The types of features considered in our experiments are summarized in Table 2.
the choice of features was motivated by our empirically driven characterization of the problem as follows: ∀i : ∃sv i o; svo(n1, v i , n2) For q2; (butterf ly, has, spots) For q2; (butterf ly, can see, spots) Noun Semantic Categories Source: we found that for verb-attaching PPs, n2 is usually a role filler for the verb, e.g., the net fills the role of an instrument for the verb catch.