The Spanish vowels are pronounced approximately in this way:
a like in English father, but shorter
o like in English saw, dawn, but shorter
e like in English pet, ten
i like in English teen, he, seed, but shorter
u like in English mood, doom, but shorter
Additionally:
i | together with another vowel (in so called diphthongs: ai, ei, oi, ia, ie, io, iu, and in : iai, uai, uei) is pronounced like English y: aire, seis, fiel, estudiar |
but í (with accent) is always pronounced like ee in "teen, see" : tranvía, oír, quería | |
u | is not pronounced after q ; after g it's not pronounced before e, i |
together with another vowel(in so called diphthongs: au, eu, ou, ua, ue, uo, ui, and triphthongs: uai, uei, uey): like English w in win, way : auto, autobús, causa, buey | |
but ú (with accent) is always pronounced like in mood, doom : ataúd | |
ü | is pronounced like English w in "win" |