dependency grammar

A type of FORMAL GRAMMAR, best known for the development it received in the 1950s (in particular, by the French linguist Lucien Tesnière (1893–1954)), which establishes types of dependencies between the ELEMENTS of a CONSTRUCTION as a means of explaining grammatical relationships. SYNTACTIC STRUCTURE is represented using dependency trees – sets of NODES whose interconnections specify structural RELATIONS. Every tree contains a GOVERNOR and a set of dependents, each of which bears a specific relation to the governor. For example, in a CLAUSE, the VERB is seen as governor, and the dependents are NOUN PHRASES, which are assigned numerical values depending on the VALENCY attributed to the verb. In a PREPOSITIONAL phrase, such as on the box, the preposition governs the noun, and the noun governs the ARTICLE. Dependencies are usually displayed as ARCS, which relate words (rather than CONSTITUENTS). The statements which specify the governing and dependent relations which each class of unit may enter into are known as dependency rules. Dependencies are of particular importance in several grammatical theories (such as DAUGHTER-DEPENDENCY GRAMMAR). The term ‘dependency’ is also used in several frameworks to express types of relationship between phrases, e.g. UNBOUNDED DEPENDENCY.