For Penn Treebank II style annotation (Marcus et al., 1993), in which a nonterminal symbol is a category together with zero or more functional tags, we adopt the following scheme: the atomic pattern a matches any label with category a or functional tag a; moreover, we define Boolean operators ∧, ∨, and ¬.
nP ∧ ¬ADV matches nP-SBJ but not nP-ADV.