AD：
把群众拉丁的元音体系简化为5个元音-- a. e, i, o, u。 五个元音的发音都清楚清楚，不管是在元音是否是在重音方位。除了a以外，古典拉丁中的短元音都在西班牙文中阅历了裂化， 如：
porta->puerta
herba->hierba
古典拉丁文中的长元音并是重音方位上的e, o在西班牙文中都被i, u替代，而短元音并非重音方位的i,u在西班牙文中被e, o替代，如：
feci->hice
重音落在词末的音节上，或是倒数第二个音节上，或是倒数第三个音节上。这个重音是在拼写中表示出来的。同古典拉丁文相比较，西班牙文的重音表现出向有r这个音的音节上靠的现象：
tenebrae->tinieblas
古典拉丁文中的元音间的子音p, t, c 在西班牙文中被浊化成b, d, g， 如：
apotheca(th等于t,由于h不发音)->bodega
元音间的d消失，如：
cadere->caer
元音间的g消失或许变成一个介音j, 写做y, 如：
legere->leer
reges->reyes
而元音间的b被保存，可是倾向于和v相同发成爆破音，如：
habere->haber
古典拉丁文中的开首的f被一个不发任何音的h替代，如：
facere->hacer
子音群ct, lt演变成ch (act成为ech), 如：
octo->ocho
multu->mucho
lactua->lechuga.
(注：这个现象便是前次我说的yod现象。子音c和l被腭化，然后变成象j相同的发音，这样yod就有条件发生了。)
子音群cl, fl, pl 腭化变成ll, 如：
clamo->llamo
flama- >llama
ploro->lloro
元音子音群ali, eli, ili, oli, uli演变成aj, ej, ij, oj, uj, 如：
alium->ajo
filius->hijo
mulier->mujer
子音群lr, mr, nr被刺进b或许d, 变成ldr, mbr, ndr, 如：
venir+he->vendre
注：这儿b, d的刺进是为了协助发音，有了b, d的介入，愈加简单发音。
以s开首的的词被加上了一个e, 如：
stare->estar
以下是原文：
SPANISH PHONOLOGY
Spanish has simplified the Vulgar Latin vocal system to only 5 open vowels (as in Classic Latin) -- a. e, i, o, u -- that are pronounced clearly and without reduction in both stressed and unstressed positions. The vowels, that are short in Classic Latin, diphthongate when stressed in Spanish except for a, cf.:
CL porta door -> Sp. puerta;
CL herba grass -> Sp. hierba.
The long stressed vowels e, o are replaced by i, u and the short unstressed vowels i, u -- by e, o, cf.:
CL fêci (I) did -> Sp. hice.
The accent may fall on the ultimate, penultimate or antepenultimate syllable. Its place is recognizable from orthography. As compared with the accent of Classical Latin, it shows a tendency to move towards a syllable containing -r, cf.:
CL tenebrae darkness -> Sp. tinieblas.
The Latin consonants p, t, c between vowels are voiced to b, d, g in Spanish, cf.:
CL apotheca (th=t) store-room -> Sp. bodega.
The intervocalic -d- disappears, cf.:
CL cadere to fall -> Sp. caer
and the intervocalic -g- may disappear or become a glide sound [j] written y, cf.
CL legere to read -> Sp. leer
CL reges kings -> Sp. reyes,
while the intervocalic -b- is preserved, but tends to become aspirated as v, cf.
CL habere to have -> Sp. haber.
The initial f- is replaced by a mute h-, cf.
CL facere to do -> Sp. hacer.
The consonant clusters ct, lt are transformed to ch (act to ech), cf.:
CL octo eight -> Sp. ocho,
CL multu(m) much, many -> Sp. mucho,
CL lactuca lettuce -> Sp. lechuga.
The clusters cl, fl, pl are palatalized to ll, cf.:
CL clamo (I) call -> Sp. llamo,
CL flama flame -> Sp. llama,
CL ploro (I) weep -> Sp. lloro.
The clusters ali, eli, ili, oli, uli are transformed to aj, ej, ij, oj, uj, cf.:
CL alium garlic -> Sp. ajo,
CL filius son -> Sp. hijo,
CL mulier woman -> Sp. mujer etc.
The clusters lr, mr, nr are divided by epenthetic -b- or -d- and become ldr, mbr, ndr, as in:
venir to come + he (I) have -> vendré (I) will come.
The words beginning with s- followed by a consonant (s impure) receive a prothetic e-, cf.:
CL stare to stand -> Sp. estar.