The article under review outlines the problems that a language teacher who works with a foreign language to foreign students may be faced. The grammar of each language is a system, but this system is, of course, specific. Different grammatical categories of language, non-identical are the general meanings by which grammatical forms are opposed to each other. It is known that with the same number of forms in different languages, their meanings can be correlated differently. In addition, homogeneous grammatical categories can be distributed unequally between different parts of speech. In some languages, affixes as morphemes, which express semantic and syntactic elements of meanings are not relationally connected to the word form and the whole system of its forms in inflectional languages – such as Russian, Ukrainian, Belarusian, etc., as well as derivational ones. Therefore, while analyzing certain languages, researchers do not describe the word change (in the broadest sense of the term), but they work with word formation, because it is the word-formation system that involve a nominal (noun, adjective, verb, numeral, pronoun) and verb paradigm, in which a "deep" morphological and syntactic system of the gender is formed and it outlines the structure, lexical and semantic components of animate and inanimate nature. Grammatical systems are different in not only grammatical meanings, but also in how these meanings are expressed. Taking into account all these features, it turns out that the grammatical system of each language is deeply unique. Despite all these features and characteristics of certain grammatical categories in the languages of different systems, we can outline that you can compare and contrast any of the existing languages, because the grammatical system of languages reveals common features that allow to develop principles for studying of universal categories. Such universals include the category of gender, which is qualified as a morphological-syntactic category of language, which realizes its potential in syntactic structures. The problem of classifying the category of gender in the languages of different grammatical systems is directly related to the research in terms of comparative and contrastive linguistics, and to the problems of studying interfering factors in language.