The article is devoted to the systematization of the domestic and foreign linguists’ scientific researches on the problem of delimiting complex sentences, as well as analysis of the historical development of classification approaches to complex sentences in Permian and Volga languages. During the research a descriptive method is used, which makes it possible to examine in detail the works of Finno-Ugric scientists such as F. J. Wiedemann, G. S. Lytkin, P. I. Savvaitov and others, whose works laid the foundation for studying the syntax of complex constructions in these language groups. Special attention is paid to various approaches to the classification of subordinate clauses: traditional, formal and structural-semantic. The article notes that in the Finno-Ugric languages, the syntactic system was formed approximately the same way. In the study of the syntactic structure of complex sentences, three main directions can be distinguished, each of which has its own characteristics and approaches. The first area pays great attention to the compositional and morphological aspects of complex sentences and is typical of the foreign linguists’ works. The second direction involves considering subordinate clauses in the context of their functional counterparts in simple sentences, which allows for a better understanding of the mechanisms of syntactic integration. The third direction is aimed at analyzing complex sentences from the point of view of structural and semantic classification. In this case, attention is paid to the relationship between meaning and form, semantics and the construction of these syntactic sentences. The study records that a deep and comprehensive study of complex sentences and their subtypes began in the second half of the XX century. There is also a special type of syntactic constructions – multicomponent complex sentences that have not previously received due attention from Finno-Ugrian scholars. The reasons for the lack of a differentiated approach to the study of such constructions and their importance for understanding the organization and functioning of complex sentences in Permian and Volga languages are analyzed. The study emphasizes that the analysis of syntactic structures of complex sentences within the framework of the Finno-Ugric linguistic paradigm is carried out synchronously with the development of grammatical theories in Russian linguistics, which allows us to identify common trends and features in the study of complex constructions in various language systems.
A. F. Utkina (Wed,) studied this question.