Language and society ; Alternation (biling.) ; Language shift (biling.) ; Sprachwechsel (biling.) ; Sprachattitüde; Linguizismus; Linguicism; Prestige; Monolinguale Ideologie; Monolingual ideology; Sprachliche Unsicherheit; Linguistic insecurity ; Transfer (second language acquisition) ; Transfer (Zweitspracherwerb) ; Cross-linguistic influence (second language acquisition) ; Interference (second language acquisition) ; Einfluss von Sprachen aufeinander (lex.) ; Languages in contact (lex.) ; Sprachkontakt (lex.) ; Lexical borrowing; Loan word ; German ; Migrant workers' German ; Italian ; Russian