same mouth position. Tt is unvoiced, meaning, only air passes through the mouth. And dd

is voiced, meaning, uh, uh, dd, you make a noise with the vocal cords. These consonants

are stop consonants, which means there are two parts. First, a stop of the airflow, and

second, a release. The airflow is stopped by the tongue position. The tongue will come

up and the front part will touch the roof of the mouth just behind the top teeth. It

will then pull down to release the air. The teeth are together, tt, and as the air comes

out, when the tongue releases, they part, tt, dd. Let's take for example the word 'pat'.

Pat: the first part, the tongue has moved up into position, cutting off the flow of

air. Pa-tt. And the second part, the tongue releases, and the air comes through the closed

teeth. A note about the teeth position for the D. As I said, the teeth are together,

tt, and part when the air is released. This must happen for a release of the T. But the

D can actually be made without the teeth coming all the way together: dad, dad. You can see

there the teeth are not closing all the way, but you're getting a D sound by the tongue

coming up into position and pulling away. Stop consonants are sometimes pronounced without

the second part, without this release, when they come at the end of a syllable or a word.

Let's take for example the sentence 'I bet you did'. I bet, you can see the tongue has

moved up into position for the T. I bet you did. But rather than releasing air through

the teeth, the mouth simply moves into the next sound, which is the 'ew' as in 'few'

diphthong. I bet you did. I bet you did. No release. It's important to note we're not

just leaving out the sound. I bet -- the tongue is moving into position, which is cutting

off the airflow. And that stop is part of the T. I bet you did. So even though we're

not releasing to give the complete full T, the idea is still there by the tongue going

into position, cutting off the airflow. So T and D can sometimes be pronounced with the

stop and the release, and sometimes just the stop. The T has another pronunciation, it's

call the flap or tap T, and on my website in the International Phonetic Alphabet, I

use the D symbol to represent this sound because it sounds and functions, and is made just

like the D. This sound happens when the T comes between two vowel sounds. Let's take

for example, the word madder and matter. One is spelled with two D's, and one with two

T's. But they're pronounced the same: madder, matter. Let's look at them in sentences. I'm

madder than I've ever been. What's the matter? It's the same sound. The lip position of these

sounds is influenced by the sound that comes next. For example, dime, dime. You can see

the mouth is taking the shape of the first sound of the 'ai' as in 'buy' diphthong, dime,

even before the D is made. Drain, drain. Again, you can see the lips taking the position for

the R, drain, even before the D is made. Do, do, again you can see the lips taking the

circle for the 'oo' as in 'boo' vowel. Do, do. Here we see the T/D mouth position on

the right compared with the mouth at rest on the left. Here, parts of the mouth are

drawn in. The soft palate is raised for these consonant sounds. The tongue position stretches

up in the front and presses against the roof of the mouth to make the stop before releasing

the air. The position is just behind the top front teeth. Sample words: time/dime, tad/dad,

tote/dote. The last two word pairs ended with T's and D's. Did you notice that I did not

release them? Sample sentence: Tom tasted Dad's dark chocolate treats. Now you will

see this sentence up close and in slow motion, both straight on and from an angle, so you

can really study how the mouth moves making these sounds. Tom, with the T, you see the

teeth close, the tongue raised behind them. And there's the release. Tom. The lips will

close for the M, and when they open you will see the teeth are still closed for the T in

tasted. Then the ST consonant cluster, and there there's a quick ih vowel, there, before

the D, tasted. Dad's. The tongue will come up here to make the D, there will be a quick

Z before the D in dark, and you can see the lips already starting to take the form of

the R even before the teeth release. Chocolate, tongue through the teeth for the L, and then

up to make the T which is a stop here. Treats, and again you see the lips forming the R even

before the teeth release the T. And the TS sound at the end. Tom, you see the tongue

tip up behind the closed teeth, releasing into the 'ah' as in 'father'. Lips close for

the M. Tasted, tongue up to make the T, quick ih sound and then the D, tasted, Dad's. Tongue

up again to make the final D. Dad's. Dark, lips taking the form of the R. Chocolate,

tongue up for the L and then to the roof of the mouth to make the stop of the T. And treats,

where the lips form the R shape around the closed teeth. And tongue tip up to make the

final T, and S sound. Treats. That's it, and thanks so much for using Rachel's English.