Composers of the 20th century variously composed Ã tudes related to the old tradition -LRB- GyÃ rgy Ligeti -RRB-, Ã tudes that required wholly unorthodox technique -LRB- John Cage -RRB-, and Ã tudes that required unusually facile technique.
Franz Liszt a Ã © galement Ã © crit des Ã tudes trÃ ¨ s difficiles. On sait que ces deux compositeurs sont non seulement bons pour la formation, mais aussi beaux.