Most western Iranian languages, despite their broad differences, show a common quality when it comes to the verbal agreement of past transitive verbs. Dabir-moghaddam (2013) and Haig (2008) discuss it as a grammaticalized split-agreement to encode S, A, and P, which is sensitive to tense and transitivity, and uses split-ergative constructions for its past transitive verbs. Laki shows vestiges of the same kind of verb-agreement ergativity (Comrie 1978) by using a mixture of affixes and clitics for subject and object marking. In this thesis, I investigate how the different classes of verbs show agreement using four distinct property classes. Considering the special case of the {3 sg} and using Hopper and Traugott's pattern for the cline of grammaticality (2003), I argue that although Laki has already lost the main part of its ergative constructions, the case of the {3 sg} marking is yet another sign that this language is in the process of absolute de-ergativization and its hybrid alignment system is moving toward morphosyntactic unity. As a formal representation of the Laki data, the final part of the thesis provides a morphosyntactic HPSG analysis of the agreement patterns in Laki, using the grammar of cliticized verb-forms (Miller and Sag 1997).

This study examines the distribution and the status of the izāfa particle in Sorani Kurdish (Central Kurdish). It uses a corpus-based analysis to investigate the forms and the pattern of distribution of the izāfa particle in Sorani, a dominant dialect of Kurdish among the Western Iranian languages. The study details an investigation of the appearance of izāfa in various NPs using a variety of data mostly from the corpus but supplemented by the grammaticality judgments of native speakers. I show that next to parallel properties seen in other Western Iranian languages, Sorani Kurdish izāfa shows a form alternation. I examine the morphological status of the izāfa and other nominal morphological features in Kurdish as well as the sensitivity of izāfa form variation to specificity in Kurdish NPs. I argue that the differences and distributional incoherence of the izāfa within Sorani and across Western Iranian languages calls for a morphomic approach, which can be formally described using a constructional approach to grammar. The study focuses on the following questions: What type of head does the izāfa mark? What is the function of this marker? What are the constraints on its distribution? What are the syntactic and morphological rules governing its distribution?