Complex sentence: The etude is a study in tremolos, but contains many other difficulties like wide jumps and fast chromatic scales, and requiring a very gentle and soft touch in the beginning it is the most difficult etude to play well save for Feux follets.
Split into simpler sentences: The etude is a study in tremolos but contains many other difficulties like wide jumps and fast chromatic scales, and it requires a very gentle and soft touch in the beginning. It is the most difficult etude to play well save for Feux follets.