Original: Composers of the 20th century variously composed Ã tudes related to the old tradition (GyÃ rgy Ligeti), Ã tudes that required wholly unorthodox technique (John Cage), and Ã tudes that required unusually facile technique.
Simplified: Franz Liszt also wrote some very difficult Ã tudes. These two composers' Ã tudes are known for being not only good for training but beautiful.