Further extension of the chromatic language finally broke with tonality and moved into the style of atonal music in the early operas of Arnold Schoenberg ("Erwartung", 1909; "Die glückliche Hand", 1912) and his student Alban Berg ("Wozzeck", 1925), both of whom adopted twelve-tone technique for their later operas: Schoenberg's "Moses und Aron", and Berg's "Lulu". Neither of these operas were completed in their composers’ lifetimes, however, so that the first completed opera using the twelve-tone technique was "Karl V" (1938) by Ernst Krenek.