A
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In FCI the slurring of the motif in b. 4-6 and 13-15 shows its microstructure as a combination of two motifs of ornamental origin:
- the nature of the first one, which is an echo of the one heard a bar before, is of a note preceded by a short grace note,
- the second one is a note preceded by a long grace note, appoggiatura.
In essence, the entire phrase could be written down as follows (the rhythmic values are halved): 
.
In the final version, Chopin simplified the slurring in accordance with the natural course of music.
See also b. 28-32.
Compare the passage in the sources »
category imprint: Differences between sources; Corrections & alterations
notation: Slurs