This is also why, unlike most Chinese music, these pieces are not written in a pentatonic scale, but in a more middle eastern style.
We can tell this because the ornamentation of these pieces is very similar to that of the bagpipes, which were invented in India, and also the penny whistle and other Celtic instruments.
Grace notes are used instead of tonguing, a technique used by the bagpipes.
These pieces were written by taking a short theme and developing it in three sections, each section adding more complex ornaments and rhythms as it progresses.
Unlike the European folk structure which normally goes ABABAB etc., as in modern pop music, Chinese folk songs have a structure of AAA, or if you count the development as a change then: ABC.