TY JOUR TI THE PROBLEM OF BILINGUALISM, DIGLOSSIA AND LANGUAGE CONTACT IN RUSSIAN AND FOREIGN LINGUISTICS KW bilingualism KW diglossia KW language system KW language contact KW the language standard KW sociolinguistic classification. JO Scientific Notes of V.I. Vernadsky Crimean Federal University. Philological sciences AU Shiyan, M.V. PY 2025 IS 11 PB V.I. Vernadsky Crimean Federal University