AEIOU

Hello everyone!

When we start learning something we say: "Esto es el AEIOU". What means "the basics".
Vowels are the very basics, and here we have:

A /a/               Pasa   /'pasa/        Shorter than a in father, slightly more open than u in cup.
E /e/                Beso  /'beso/        English e in pen
I /i/                  Fin     /'fin/            Shorter than English ee in seen.
                                                   Longer and more closed than English i in sin.
O /o/               Oso  /'oso/           Shortet than English o in rose, and without the /U/ sound.
                                                   When in a syllable wich ends in a consonant.
                                                   It is closer to British English o in dot.
U /u/               Uno /'uno/             Shortet than English oo in boot.
                                                   Longer and pronunced with more rounded lips than English oo in foot.

A is also a preposition.

No one of them correspond exactly to an English vowel.
They have the same quality as stressed vowels.
There is slight variations e.g. determined by their context, but never serve to distinguish one word from another.