Consonant alternations in changing verb forms in modern Russian

The article is devoted to consonant alternations in the verbal final basis that is associated with the processes of verbal form changes. It presents some results of the verbal form analysis that are being conjugated as types 4-8. The source of the material was “Grammatical dictionary of the Russian language” by A.A. Zaliznyak. It is proved that the alternation in verbal forms of modern Russian depends on the character of language levels coordination thus performing the following functions: grammar meaning intensification, lexical homonyms differentiation, and grammar form identification including. The novelty of the data presented in the article consists in defining the principle statement that there exists some variations in the balance between regularity and predictiveness of consonant alternations in verbal forms: the alternation is more predictable if the number of grammema clusters in a paradigm that they mark is lower (type 4 with inflection - ить ); on the contrary, the less predictable the alternations are, the bigger grammema clusters in the paradigm are, (i.e. when used for intensifying type 6 (with inflection - ать ). The comparison of verbal forms with and without alternations resulted in the following conclusion: an infinitive form of a verb will predict with greater certainly types of alternations in the final basis and point to a definite kind of morphological meaning. The regularities revealed might be used in a descriptive morphology of modern Russian and in practice of teaching Russian as a foreign language.