More prominent parts of the phonological phrase, and of the sentence itself, tend to be situated toward the "right." In other words, elements that seem to be more important, vis-a-vis other elements, will tend to come later, at every level of the hierarchy. This has important implications for meter and its relation to syntax. Take the Spanish 11 syllable line:

El dulce lamentar de dos pastores.

The last part of the line is more constrained, the earlier part relatively freer. To analyze it we should start at the end, not the begining. The line is defined by the accent on the 10th syllable: "pas-TO-res. (The 11th syllable can never have an accent.)

Since Spanish tends to avoid accented syllables next to each other, the 9th syllable will usually be unaccented as well.

The canonical accent for this line is on the 6th syllable. El dulce lamen-TAR. So we can predict that syllables 5 and 7 will also be unaccented. What about 8? You guessed it: it is permitted, but not required, to have an accent on syllable 8. In the case of this line, the accent on the word "dos" is light.

That leaves the first four syllables unaccounted for. The variation in rhythm in this line stems from the fact that any of the first 4 syllables may bear an accent. There is probably a statistical preference for the even numbered syllables (2 and 4).

When the main accent is on 4, this can have the tendency to push back the accent on 6 unto syllable 8.

The entire line quoted above is a noun phrase, consisting of a noun-phrase + a prepositional phrase. Within the line, this prepositional phrase is more accented than the initial noun phrase. El dulce lamentar DE DOS PASTORES.

Likewise, the prepositional phrase consists of the preposition + a noun phrase: de DOS PASTORES. The noun phrase "dos pastores" is also weighted to the right "dos PASTORES."

The noun-phrase "el dulce lamentar" is also weighted to the right: "el dulce LAMENTAR."

This is a round about way of saying that the phonological and metrical structure of the line obeys the logic of its syntactical structure.