Diana Szewczyk

The pronunciation of words ending in 'ED' depends on the final consonant sound. There are three ways to pronounce 'ED' at the end of a word in English:

/id/          /t/         /d/

If the word ends on T or D, we pronounce the 'ED' ending as /id/. 

For example: WANTED, NEEDED. 

If the word ends on voiced sound, which uses the vocal cords and produces a vibration or humming sound in the throat (touch your throat to feel it), we pronounce the 'ED' ending as /d/.

If you cannot recognise the voiced sound from vibration in the throat, you can simply remember that they are the following letters which produce this sound such as: L, N, R, G, V, S, Z, B, M and all the words that end in a vowel sound: A, E, I, O, U, Y (it is a vowel in English!) and W (it is a consonant with the vowel sound). 

For example: CALLED, CLEANED, OFFERED, DAMAGED, LOVED, USED, AMAZED, RUBBED, CLAIMED, FOLLOWED, ENJOYED, PLAYED, TRIED, CONTINUED. 

If the words end on voiceless sound such as: P, K, F, GH, SH, CH, SS, C, X, we pronounce the 'ED' ending as /t/. Voiceless sound means that it does not produce any vibration in the throat, again if it is too difficult for you to recognise it, you can just learn by heart the letters above.

For example: HELPED, LOOKED, SNIFFED, LAUGHED, WASHED, WATCHED, KISSES, DANCED, FIXED.  

Below you can see a table that can help you to organise better the information. At the beginning, it looks complicated, however, with time you are going to realise that it is almost impossible to pronounce these endings differently. 

I recommend you to practise some listening exercises, for example from BBC website for studying English:

BBC - Learning English (ED - exercises)