A Study of Relative Clause Extraposition in Persian Based on Discourse Grammar

This paper sets to explore the extraposition of relative clauses in Persian based on Discourse Grammar (DG). In this phenomenon, the relative clause moves from the adjacency of Head Noun and is positioned at the end of the sentence leading to discontinuous construction. DG organizes linguistic elements into two domains according to their prosodic, syntactic and semantic behaviors, namely Sentence Grammar (SG) and Thetical Grammar (TG). Given that TGs are not governed by the structural requirements of SG, they, as properties of thetical elements, tend to be positionally mobile. By analyzing different instances of relative clauses in Persian, this paper then shows that the phenomenon of extraposition is a common property of relative clauses. In short, the mobility of nonrestrictive relatives results from being belonged to the thetical domain, while the mobility of restrictive relatives as elements of having been transferred from TG to SG domain by grammaticalization, is described as the persistence of the property of earlier form in the new construction.