Free Sounds Guidebook

How to Pronounce the OH /oʊ/ Diphthong

(Video Transcript)


Introduction to diphthongs

In previous videos, I talked about the American English vowels, like the AH in father and the UH in butter. In this video, I’ll talk about another set of American English vowels, called diphthongs. A diphthong is a vowel that is made of two vowel sounds, like the AY in late, or the OW in how. Since there are two sounds in a diphthong, that means there needs to be movement of the articulators, from the first vowel position to the next. The jaw might close more as you say the sound, or the lips might round more. The important thing is there needs to be movement as you say the sound - from the first position to the last position. AY, late. OW, how.


If there isn’t any movement, then you’re not pronouncing the diphthong correctly. In that case, you may be pronouncing the vowel like a monophthong, which is one vowel sound only, like the AH in father and the UH in butter. 


But diphthongs are two sounds - so there needs to be movement.


Today I’ll discuss how to pronounce the diphthong OH /oʊ/ as in no


How to pronounce OH /oʊ/

Watch my mouth as I say OH. OH. Two things are changing: my jaw and my lips. Watch again: OH. For the first part of the sound, my jaw is open, and my lips can be relaxed or slightly rounded, like this. Then for the second part of the sound, my jaw closes and my lips round, like this. OH. OH.


Slow down and exaggerate the movements at first - OH, OH - until you feel like you understand the two parts of this vowel. OH. OH. Focus on the transition between the first and second sound - OH. Then you can speed yourself back up, OH.  But stay focused on the changes in the jaw and lips. Practice in front of a mirror so you can see the movements. OH. OH.

OH diphthong in slow motion

Here is a close up of the OH sound in slow motion. The jaw is open and the lips are relaxed at the beginning of this sound, then the jaw closes and the lips round.


Here is the word toe in slow motion. My lips are a little flared out because of the T sound that comes before the vowel. Whenever two sounds are next to each other, like the T and OH sounds in the word toe, one sound can affect how the other is pronounced. This is called coarticulation, and it is very common in speech. In the case of toe, the coarticulation effects of the T don’t change the sound of the OH diphthong, just the lip placement at the beginning of the vowel.  Then the lips round at the end.


Now watch my lip position in the word show. You can see the effects of coarticulation again, as the lips are flared out because of the SH sound that comes before the vowel. This doesn’t change the sound of the OH diphthong. And my lips round at the end. 


Stressed OH vs. Unstressed OH

In a stressed syllable, the pitch of my voice glides up and then down as I say OH, OH. No. Show


But in an unstressed syllable, the OH vowel is pronounced at a lower pitch with a flatter shape and it’s said for a shorter duration. OH. OH. 


Let’s compare the stressed OH in show to the unstressed OH in meadow


On the top is the stressed OH in show, and on the bottom is the unstressed OH in meadow. Notice the difference in jaw opening and lip rounding between the stressed and unstressed OH diphthongs. The unstressed OH has less jaw opening and less lip rounding.


In English, it is common to reduce or simplify the pronunciation of vowels and diphthongs when they are in the unstressed position. So in the case of the OH diphthong, there is less jaw drop and less lip rounding. Native speakers do this because unstressed syllables are said faster than stressed syllables, so the pronunciation of unstressed syllables is simplified.


Stressed OH. Show. Unstressed OH. Meadow.


Practice words and sentences

Here are practice words and sentences:


Phone. OH. Phone.

I’m talking on the phone.


Close. OH. Close.

Please close the door.


Knowing. OH. Knowing.

There was no way of knowing what was on his mind.


Obey. OH. Obey.

You need to obey the law.


Tiptoe. OH. Tiptoe.

She stood on tiptoe to reach the cookie jar.


Hotel. OH. Hotel

Our hotel is on Park street.

Thanks so much for watching! And I'd love to hear from you - contact me to learn how we can work together to perfect your American English pronunciation!


Julie Cunningham | San Diego Voice and Accent Julie Cunningham | San Diego Voice and Accent Julie Cunningham | San Diego Voice and Accent

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