the use of vowels is the same as English is, it takes at least one consonant and a vowel to form a syllable, although there are some consonants as "Y" that its phonetic sound is equal to "I" words example, ley and hay, this consonant at the end of the word sounds like "i" and when we say for example Antonio y Juan this sounds like "i", but his combined on a vowel sound phonetic change. vowels are divided into weak (u, i) and strong (a, e, o) or closed and open vowels.

a=like the "a" in "car" never sounds like "ei" as "ame" e= like the e of "earth" never sounds "i" as "feel" or "need" or "we" and the "e" in the end of a work cans be pronounced. i= sounds as "y" in "sorry" never sounds "ai" as "life" o= like the "o" in "closed" u=like the "u" in "saturday" espero haberme expresado bien para poderte ayudar y si me equiboco entonces que me corrigan