a – pronounced like short a in “father”: mama
e – pronounced like short e in “red”: pole
i – like long i in “sleep”, but pronounced short: wino
o – is pronounced short, like aw in "dawn": tona, morze
ó – like short u: mól, pól
u – is pronounced like oo in "mood", but short: duży, lutnia
y - very open i: ryba
The pronunciation of u and ó is identical in Polish.
Before a vowel, i is pronounced as j or just denotes the softness of the consonant: piasek, ciało.