These two sounds can be difficult for ESL students to tell apart, depending on where they come in the word. To make things even more difficult, we often don’t really say either of these two sounds. Instead, we compromise, and say a sound that is a variation, called a flap. In a flap, the tongue is flicked against the top of the mouth behind the top teeth, and then immediately brought back down again.
Confused? Don’t be. Just watch the video!
The first pair of consonants we’re going to look at is /t/ and /d/. So, /t/ is voiceless and /d/ is voiced. The front of the tongue is raised and stops air from coming out – this is true for both of them – remember the only difference is whether they’re voiced or not. The sound is made when the tongue moves down and the air is released. So for /t/ it’s only the aspiration for /d/ there’s also the voicing. Both /t/ and /d/ are clear in word initial position: tire, dire. You hear both of those and they’re quite clear. If it’s between vowels in an unstressed syllable /t/ will often sound like /d/ so – now this isn’t true for every dialect but again it’s true for what I speak, which is standard North American. Water. Water. Now in some parts of the world they might say water and that might be a clear T but not in most of North America. Water. The next word: computer, computer. Again, it sounds more like a D and, now, listen carefully here to what goes on with this word: potato, potato. This one – potato, potato – sounds like a clear T. This one sounds like a D, sounds like a /d/. Well, why is that? Potato, potato. Well, the answer is right up here. It’s whether or not something is in an unstressed syllable. So potato this T is pronounced like a t – this is unstressed so it’s pronounced like a /d/. Potato, potato. /t/ is often not aspirated at the end of a word and /d/ is often very quiet. So, if the word is by itself, it’s more likely you will hear it, but if there’s another word or the sentence continues after that it’s much less likely. So listen carefully: goat skin goat skin. You can’t hear that T because I didn’t say it. Goad him into, goad him into. So there we did hear the D a little bit – goad him into. Here it disappears. Well, if this one is hard to hear and this one isn’t there at all, how do we know what you’re saying? The answer is you have to listen to the vowel that comes before. If it’s a shorter vowel sound it’s going to be a voiceless consonant. If it’s a longer vowel sound, it’s going to be a voiced consonant, so I kind of have to work backwards. All right which is the last point that I have going here. Notice how the /t/ or /d/ changes how long the vowel is. All right, I’m going to read a list of words that have the /t/ sound in them. Over here on this side it says initial. That means to come at the beginning of the word. Medial in the middle and then final…I bet you can figure that one out. It means at the end of the word. So I will start over here. If you want to repeat, you can stop the video. I’m going to leave a pause but not not too long. Here we go: team, tax, teeth, tame, take. Now for medial: litter, writing, lightest, yeah you notice that you can hear this one clearer more clearly than you can hear this one. Lightest, lightest, dirty, dirty. Again stress is out here, so this ends up sounding like a /d/ instead of a /t/. Hurting, hurting. And we’ll now listen to it final, word file position. These ones, they come at the end of the word and there’s no no sentence that continues afterwards so it’s probably going to sound much clearer: pet. On the other hand, if I said – if I said this, if I said pet food, pet food, I probably wouldn’t hear that T but because this comes at the end, there’s nothing that goes afterwards. Excuse me. You’re not going to hear the T as clearly. So, once again here: pet, pet food, got, wet, but, and sit. All right this is a YouTube budget; I don’t I don’t do things again! All right, now, I’m going to read some words that have a /d/ sound. We’re going to go through the same progression: deem, dike, dale, dim, dose. Medial: loading, ruder, coded, body, moody. And word final position: need, mad, kid, toyed, speed. Okay, so do you think you’ve got that? Let’s see. I have a list of words here that are what we call minimal pairs. They’re the same except for one sound. Now the spelling isn’t the same but – sometimes it is – but it’s not always but the sound is except for one sound, okay? So we can see here I’ll circle whole world there. We can see those words are the same except for, well, except for the one sound that isn’t. So, I’m going to say either this one or this one, and I want you to remember which and then I will give you the answers. Let’s begin: team, team; dip, dip; lid, lid; bat, bat; head, head; right, right; slight, slight; tend, tend; tear, tear – sorry, that word can be pronounced more than one way; I had to make sure I was going to say it the right way – and finally, toes, toes. All right here’s the answers. The words that just – whoops! – the words that just got a little bit bigger are the ones that I said. How did you do? Okay, thank you very much see you next time.