(1) Two contiguous strong vowels before the accent naturally form two
syllables; e.g., _lealtad_, _roedor_ are properly trisyllabic. But
synæresis is possible, especially where _e_ is one of the vowels.
(2) If the first of two contiguous vowels before the accent is strong
and the second is weak, they naturally form a diphthong; _v[ai]vén_,
_p[ei]nado_. They are regularly in distinct syllables, however, when the
first vowel (except _a_) is part of a prefix, as in _preinserto_,
_prohijar_, _rehusado_ (prefixes _pre-_, _pro-_, _re-_). Nevertheless,
synæresis is here permitted, and the diphthong is normal where _a_ is
the vowel of the prefix, as in _[ai]rado_, _[ahu]mado_.
(3) Usage varies when of two contiguous vowels before the accent the
first is weak and the second strong. The derivative follows the simplex;
thus the _i_ and the _a_ are in separate syllables in _criador_ and
_criatura_ because they so stand in _criar_, they form one syllable in
_cambiamiento_ because they do so in _cambiar_. But synæresis is always
possible where the diphthong does not already exist.
(4) If both the contiguous vowels before the accent are weak, they
naturally form a diphthong, as in _c[iu]dad_, _c[ui]dado_. Derivatives
of words of variable syllabification may imitate their simplex: thus
_viudo_ may be either dissyllabic or trisyllabic (cf. I, rule 7) and
_viudez_ has the same liberty.