a default central form-meaning pairing from which all instances inherit their features. It thus operates with a fairly high level of generalization, but does also allow for some redundancy in that it recognizes extensions of different types. Complete inheritance model In the complete inheritance model, information is stored only once at the most superordinate level of the network. Instances at all other levels inherit features from the superordinate item. The complete inheritance does not allow for redundancy in the networks. Principle of no synonymy Because construction grammar does not operate with surface derivations from underlying structures, it adheres to functionalist linguist Dwight Bolinger's principle of no synonymy, on which Adele Goldberg elaborates in her book. This means that construction grammarians argue, for instance, that active and passive versions of the same proposition are not derived from an underlying structure, but are instances of two different constructions. As constructions are pairings of form and meaning, active and passive versions of the same proposition are not synonymous, but display differences in content: in this case the pragmatic content. Some construction grammars As mentioned above, Construction grammar is a "family" of theories rather than one unified theory. There are a number of formalized Construction grammar frameworks. Some of these are: Berkeley Construction Grammar Berkeley Construction Grammar (BCG: formerly also called simply Construction Grammar in upper case) focuses on the formal aspects of constructions and makes use of a unification-based framework for description of syntax, not unlike head-driven phrase structure grammar. Its proponents/developers include Charles Fillmore, Paul Kay, Laura Michaelis, and to a certain extent Ivan Sag. Immanent within BCG works like Fillmore and Kay 1995 and Michaelis and Ruppenhofer 2001 is the notion that phrasal representations—embedding relations—should not be used to represent combinatoric properties of lexemes or lexeme classes. For example, BCG abandons the traditional practice of using non-branching domination (NP over N' over N) to describe undetermined nominals that function as NPs, instead introducing a determination construction that requires ('asks for') a non-maximal nominal sister and a lexical 'maximality' feature for which plural and mass nouns are unmarked. BCG also offers a unification-based representation of 'argument structure' patterns as abstract verbal lexeme entries ('linking constructions'). These linking constructions include transitive, oblique goal and passive constructions. These constructions describe classes of verbs that combine with phrasal constructions like the VP construction but contain no phrasal information in themselves. Sign Based Construction Grammar In