Linguistic institutions ; Bundesrepublik Deutschland; Federal Republic of Germany; BRD; Germany ; Great Britain ; Educational policy ; Second language acquisition (language teaching) ; Zweitspracherwerb (Unterricht) ; Foreign language teaching ; DaF; Deutsch als Zweitsprache; German as a second language; DaZ; German as a foreign language ; English as a second language; ESL; TESOL ; Language planning; Purification of language; Sprachpurismus; Sprachverfall; Language decay; Language cultivation ; German ; Mandarin; Kantonesisch; Cantonese; Putonghua; Sinitic; Hakka; Yue; Chinese