There are three pronunciations of the 'ed' in regular verbs: 1. As you say, the easiest group are the verbs which end in 'd' or 't' in the infinitive, like 'want' and 'need'. These have an extra syllable in the past simple, pronounced 'id'. So 'wanted' is two syllables, pronounced 'wont-id'. 2. Most verbs simply add a 'd' sound to the final syllable, but it's not difficult to pronounce. Can you say the word 'and'? Of course you can. So if you can say 'and', you can also say 'canned', 'planned, 'scanned' and the past simple forms of all sorts of other verbs which end in 'n'. The sound at the end of the word is the same. Likewise, if you can say 'cold', you can also say 'called', 'rolled', 'filled' and any other past participle with an 'ld' sound at the end. 3. With verbs ending in 'p' 'f' 's' 'k' 'sh' 'ch' and 'th' sounds, the final 'ed' in the past simple sounds like a 't'. But again, there's no mystery about how to pronounce these words. Can you say the word 'past'? Well, if you can say 'past', you can also say 'passed'. In fact, the words 'past' and 'passed' sound exactly the same. When we say 'past' or 'passed' it is impossible to know which word is being said. So, as you can see, there is no need for past forms to slow you down. The pronunciation of the word 'played' is no longer than the the word 'play'. And your tongue IS used to making these sounds. If you can say 'past', you can say 'passed', and if you can say 'band' you can say 'banned' - these words sound exactly the same. I hope that helps.

With those ones, I pronounce them with a 'de' at the end. The sound is separate to the first part, and slightly voiced. It's a little like the '-ded' sound of the previous ones, but without the final 'd' sound.