The article analyzes the communicative universe of the speech norm in its sociocultural, linguistic and cognitive aspects. The authors emphasize that it is not enough for the interlocutors to know only the grammatical system of the target language in order to adequately understand each other. Reflecting on the problems of the communicative norm formation, the authors expand the methodological field of research and "bring" the learner into the so-called communicative space, which must be built taking into account a complex of linguistic, speech, intercultural, and ethnopsychological components. The authors consider the phenomenon of interference as one of the main didactic problems faced by Russianists, linguists, sociologists, and linguopsychologists. Interference as a linguistic, sociocultural and ethnopsychological phenomenon is in the focus of many boundary sciences about the language and the homo loquens (speaking man). The article analyzes errors related to the problem of interference at the orthoepic, spelling, lexical, morphological, syntactic, and discursive language levels. In addition, specific methodological recommendations are given on how to remove interference phenomena in order to develop the students' communicative competence in the target language.