Why and how do Hebrew verbs change their form? A morpho-thematic account

This paper examines the criteria that are responsible for morphological variation in the verbal system of Modern Hebrew. The Hebrew verbal system consists of configurations called binyanim (and binyan in sg.): CaCaC, niCCaC, hiCCiC, CiCeC and hitCaCeC. The relation between Hebrew binyanim is manifested via valence changing operations (e.g. nišek 'kiss' and hitnašek 'kiss each other'). Some verbs demonstrate morphological variation with regard to their binyan. I define morphological variation as cases where two verbs occur in (at least) two different binyanim, but share the same (i) stem consonants (ii) thematic grid and (iii) denotation. For example, the verbs nirtav and hitratev are formed in niCCaC and hitCaCeC respectively; they are both intransitive verbs that denote 'get wet' and they share the stem consonants r-t-v. Morphological variation results from a change that takes place in the verbal system, where a verb takes another form. I analyze the factors that bring about the development of a new morphological form alongside the existing form, and are responsible for the choice of a specific binyan during that process. The main claim is that the addition of another binyan results from both morpho-phonological and thematic-syntactic factors. With respect to the former, the morphological mechanism changes the binyan of verbs in cases where their inflectional paradigm consists of prosodic or segmental alternation. With respect to the latter, verbs that are stored in the lexicon as thematically derived entries have a greater chance of undergoing binyan change than do basic entries. Verbs that are the output of syntactic operations do not undergo morphological change. In addition, verbs which are morphologically neutral with respect to transitivity change into a binyan that is marked as transitive or intransitive.