objects, like “verb” and “noun-phrase.” The abstract objects are fully described by their properties and their values. Multiple descriptions for the properties and values of the abstract linguistic objects are presented in the literature. Examples are:

1.  Feature graphs, which are labeled rooted directed acyclic graphs $G=(V,A)$, where $F$ is a collection of labels, a sink in the graph represents an atomic value and the labeling function is an injective function $f:V\times A\mapsto F$.

2.  Attribute-value matrices, which are matrices in which the entries consist of an attribute and a value or a reentrance symbol. The values are either atomic or attribute-value matrices.

From a computational point of view, all descriptions that are used in practical problems are equivalent. Though there exist some theories with a considerably higher expressive power [@blackburn.ea:93]. For this paper we adopt the feature graph description, which we will define somewhat more formal in the next section. Attribute Value Languages(AVL) [@smolka:92] consist of sets of logical formulas that describe classes of feature graphs, by expressing constraints on the type of paths that can exist within the graphs. To wit: In a sentence like “a man walks” the edges labeled with “person” that leave the nodes labeled 