Micro study 8 is the next event to this etude, and in many ways it should pose no problems if you have played etude no. 4. Here we have another version of the diminished 7 chord shape being shifted up and down the fretboard in a set of intervals. If we consider the chromatic alterations as approach tones, then all Villa-Lobos is doing is another whole tone fragment (F G A B C#) which is approached from the note above. They are also on main beats.
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