One of the most difficult problems for non-native speakers is facing English pronunciation. It is nearly always a hard obstacle to overcome. But anyway, you'll be able to improve your pronunciation if you practise it a lot and follow some tips such as these ones ...
Well today, let's focus on pronuncing -ED endings!
There are 3 different ways to pronounce -ED ending of regular verbs in the Past Simple:
1. /id/ when the base form of the verb ends in /d/ or /t/, such as NEED - NEEDED /id/, WAIT - WAITED /id/.
2./d/ when the verbs end in a voiced consonant or a vowel (since all vowells are voiced). To check if a consonant is voiced, you can put your hand on your throat, pronounce the verb and feel the vocal cords vibrating. Let's see some examples: CALL - CALLED /d/, LOVE - LOVED /d/.
3. /t/ when the verbs end in a voiceless consonant, so the vocal cords never vibrate when you pronounce these verbs, such as: KISS - KISSED /t/, LOOK, LOOKED /t/.
Now, look at the Woodward Chart which can help you to practise the -ED endings prnounciation.
At last but not least, you can do the following listening tests, click here: bbc.co.uk, cisl.edu/wordpress/listening-practice