It's hard to say that I passed very time hearing and saying "I WOURQUEEDI (I WORKED) or I WOTIIDI (I WATCHED)", when I didn't know that the Irregular Verbs have three ways to be pronounced.
So, I will try to show you. Pay attention:
1 - When the Regular verb ends in a vowel sounds or voiced consonat (B,G,L,M,N,V,Y and Z), the -ED is pronounced D.
EX: PLAYED, TRAVELED.
2 - When the Regular verb ends in an unvoiced cosonant sound (K,P,F,-SH,-TCH, or X) the -ED ending is prounounced T.
EX: WORKED, WATCHED, FIXED
3 - The -ED ending is pronounced ID when the Regular verb ends in consonat sounds D or T.
Ex: NEEDED, ALERT.
It's just study, see ya.
Christian Nunes.