Answer to Question 1
A repetitious melody is made up of recurring phrases.
The bimodality' of a constant alternation between the major and its relative minor keyis characteristic of both northern Ecuadorian highland sanjun, and many other Andean traditional musics.
Answer to Question 2
0:000:43 Introduction by harp (Efran) There is a strong, characteristic rhythm in the first four beats of the song's main phrase: long-long-short-long-short-long-long-longer identified in WOM as Ta Ta Ta-Ta, Ta Ta Ta Ta. During the next four beats, which constitute the second half of the main phrase, this rhythm is repeated exactly, creating isorhythmic phrases. Some combination of sixteenth-eighth-sixteenth, and two eighths, short-long-short, long-long is characteristic of most sanjuanes. (Try tapping this repeating rhythm with the harp so that you get the feel of the pattern. See also answer to question 33, below.)
Golpe, rhythmic hitting on the harp sound box by a golpeador--in this case, by the vocalist, Rafael--helps reinforce the beat and keep the tempo rock steady.