Spanish vowels are divided into two categories: hard and soft. Hard vowels (A,
O, U) cause the consonant that precedes them to be pronounced with a hard sound,
which I've abbreviated in this lesson as [HS], while soft vowels (E, I) are
preceded by a soft sound [SS]. (Note that consonants - R, L, etc. - are always
preceded by the hard sound.)
The consonants affected by this hard/soft distinction are C, G, and, to a
lesser extent, Z.*
*The letter Z is a hard consonant, meaning that it Z has no "soft"
pronunciation and, with very few exceptions, cannot precede an E or an I; it
must be replaced by the letter C (as explained below).
* * *
Some Spanish words need a hard sound in front of a soft vowel, or a soft
sound in front of a hard vowel. This is the reason behind many Spanish
spelling changes in plurals and
irregular verb conjugations (mostly in the
and subjunctive). For
certain plurals and verb conjugations, it is necessary to change the
spelling in order to maintain a hard sound in front of a soft vowel or a
soft sound in front of a hard vowel.