This is what I have been explaining in class... Printer-friendly version (2 pages)
Quick Guide: NEVER pronounce /ed/!!! Pronounce a /t/ instead!
Before telling you when to pronounce a /t/ or when to pronounce a /d/, let us see what happens to a small but commonly used group of words - the words whose infinitive form ends in a dental sound (t or d).
Now we need to integrate those isolated words in connected speech! So...
When to say /t/ or /d/
When to pronounce the "-ed" as a /t/ and when to pronounce it as a /d/?
If the last SOUND in the infinitive form (the form without the -ed ending) is a vowel or a voiced consonant, the -ed should be pronounced /d/.
If the last SOUND in the infinitive form (the form without the -ed ending) is a voiceless consonant, the -ed should be pronounced /t/.
IF YOU HAVE NO TIME TO WORK THAT OUT, PLEASE PRONOUNCE A /t/, a strong dental sound, so that it is clear to the listener that you are not using a present or infinitive form! This was my first tip when you started reading these notes, wasn't it?
To find out which are the voiced and the voiceless consonants, you need to do the following exercise:
Feel your throat with your fingers until you find the exact place where the vibration you can notice comes from. That place is where your vocal chords are.
Say different vowels. All vowels, both in Spanish and English, are VOICED, which means, our vocal chords vibrate when they are pronounced.
Is your hand in the correct place? OK then, now, to the consonants.
Being careful of not saying any kind of vowel sound, say /k/
Your vocal chords don't vibrate, so /k/ is a voiceless sound.
Say /v/. Your vocal chords vibrate, so /v/ is a voiced sound.
Pronounce this (both): ask - asked. Did you say "asked" or "askt"? The first is IMPOSSIBLE in English because we never pronounce a Spanish "e", we cross out the vowel, so to say. And because /k/ is voiceless, the dental sound in the -ed ending is pronounced as a /t/ (voiceless dental).
Pronounce this (both): receive - received. Did you say "risiived" or "risiivd"? The first is IMPOSSIBLE. Because /v/ is voiced, the dental sound in the -ed ending is pronounced as a /d/ (voiced dental).
Anyway, you want a list! I know. Please, practice feeling your chords as you pronounce each and every one of them. If you have any trouble with the pronunciation of any, tell me in class!
Voiced sounds (-ed as d)
All the vowels!, like...
play - play
ed /pleid/ NEVER "plalled"!!!
stay - stay
ed /steid/ NEVER "stelled"!!!
bow – bow
ed /baud/ NEVER "bogüed"!!!
argue - argu
ed /aargiud/ NEVER "argued"!!!
continue - continu
ed /kontiniud/ NEVER "kontinued"!!!
And verbs/adjectives ending in voiced consonants
change - changed
log - logged
fill - filled
jam - jammed
pin - pinned
receive - received
buzz - buzzed (this is no “zeta” sound, but a voiced “s”)
is voiced, but its usually at the beginning of words: the, these, this, that...
Voiceless sounds (-ed as t)
watch - watched
laugh - laughed
ask - asked
stop - stopped
pass - passed
wash - washed
is voiceless, but I can't think of verbs/adjs ending in this sound! (through, thin...)