[θ] and [ð] are paired together because they take the same mouth position. Learn the correct mouth position for these sounds to pronounce them clearly and accurately.
The two TH consonant sounds. These sounds are paired together because they take the same mouth position. Th is unvoiced, meaning, only air passes through the mouth, and th is voiced, meaning you make a sound with the vocal cords. To make this sound, the very tip of the tongue comes through the teeth, th, th, thanks, th, th, this. The rest of the mouth remains relaxed. For the THR consonant cluster, the lips will begin to move into position for the R while the TH is being made. Three, three. In some cases, these sounds will be replaced with a similar sound, when the tongue does not quite come through the teeth. Instead it presses against the closed teeth. This will happen in an unstressed word only, when there isn’t enough time given to the word for teeth to part and the tongue to come through. For example, ‘What’s in the car?’ What’s in the car? The tongue isn’t coming all the way through the teeth.
Here we see the TH sound on the right compared with the mouth at rest on the left. And with parts of the mouth drawn in. The soft palate is raised for this sound. You can see the tongue through the teeth, just the tip comes through. The TH consonant sounds. Sample words: thin/this, thief/these, birthday/worthy. Sample sentence: I thought of using these Lily of the Valleys rather than those thorny roses. 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 when making these sounds.
I, with the ‘ai’ as in ‘buy’ diphthong. Thought, tongue tip through the teeth, TH, thought. ‘Aw’ as in ‘law’, tongue up to make the T which is a D here, thought of. Using, the ‘ew’ as in ‘few’ diphthong. These, tongue tip through the teeth. Lily of the Valleys, tongue up in the L position, comes down, ‘ih’ as in ‘sit’, back up for the second L, lily, of, bottom lip up for the V sound, and again for the V sound of Valleys. Tongue up for the L, that was an L, not a TH. Rather, lips take the R consonant shape, and the tongue comes through the teeth again for the TH, one more time quickly for than. Those, ‘oh’ as in ‘no’ diphthong, and again for thorny, thorny roses, R consonant shape, ‘oh’ as in ‘no’ diphthong. Teeth together for the Z sound, then part slightly for the schwa, and together again for the final Z sound. And now from an angle. I thought, tongue tip through the teeth, tongue up to make the D sound, bottom lip up for the V. Using, with the ‘ew’ as in ‘few’ diphthong. These, tongue tip through the teeth. Teeth together for the Z sound and tongue up to make the L. Lily, up again for the second L. Lily of, bottom lip up for the V. And you don’t even seen the tongue for the TH there because it’s so quick. Of the Valley, Valleys. Rather, mouth takes the R consonant shape and the tongue tip comes through for the TH. Rather. The tongue tip comes through quickly to make than and those, than is very short there. ‘Oh’ as in ‘no’, teeth together for the Z sound. Thorny, tongue through the teeth for the TH, tongue up to make the N, roses. R consonant shape, teeth together for the Z sound, part for the schwa, and together again for the Z sound. That’s it, and thanks so much for using Rachel’s English.