Instruction (medium of) ; Medium of instruction ; Amtssprache; Official language; National language ; Sprachenpolitik; Language management; Language politics ; Multilingualism; Polylingualism; Plurilingualism ; Sprachentod; Extinct language; Language endangerment; Bedrohte Sprache; Linguicide; Linguizid; Language death ; Hochsprache; Schriftsprache; Acrolect; Standard language ; Lėtzeburgesch; Luxemburgisch (deutscher Dialekt) ; Luxembourgish ; Luxembourgeois