Free Sounds Guidebook

How to Pronounce the OY /ɔɪ/ Diphthong

(Video Transcript)

The Diphthong OY /ɔɪ/

Listen to how I pronounce the word boy. The vowel, OY, has two sounds. This is because OY is a diphthong vowel. Diphthongs are made of two sounds, so that means each diphthong has a starting position and an ending position. You should feel your articulators move as you say the sound.


The first part of the OY diphthong is the /ɔ/ vowel. This is a vowel that I don’t teach in its pure form because I don’t use the vowel /ɔ/ by itself. In some areas of the United States, the /ɔ/ vowel has been replaced by the /ɑ/ as in father vowel. I pronounce the words hot and doll with the same vowel as law and talk. The only time I use the /ɔ/ vowel is in the diphthong /ɔɪ/ and the R-colored vowel OR /ɔɹ/.


Pure vowels vs. diphthongs

When a vowel is part of a diphthong, sometimes it doesn’t sound as pure as it does when it is by itself. The OY diphthong is made up of these two vowels, /ɔ/ and /ɪ/. The first part, /ɔ/, has the lips more rounded when compared to the pure vowel. And the second part of the diphthong, /ɪ/ as in bit also changes. The jaw is a little more closed and the tongue is a little higher in the final sound of OY when compared to the pure IH vowel. 




You don’t need to focus any of your time on why these vowels sound different in a diphthong. Focus on making the correct movement of your mouth as you glide through the diphthong, and then you’ll be making the correct sound. 


How to practice diphthong vowels

When you are first practicing how to pronounce a diphthong, you should hold out the sound and exaggerate the movements. 




Until you feel like you understand the two parts of this vowel. Focus on the transition between the two sounds.




Then you can speed yourself back up.




Watch my mouth position as I say the word boy. At the beginning of the vowel, the lips are rounded, and the tongue is pulled back. Then as I progress to the second sound of the diphthong, the jaw opens and the lips pull back and relax. You can see the tongue moves forward and arches up towards the roof of the mouth. 


Stressed OY vs. Unstressed OY

When OY is in a stressed syllable, the pitch of my voice glides up and then down. OY. Boy.


But in an unstressed syllable, the OY vowel is pronounced at a lower pitch with a flatter shape, and it is quicker. OY. OY.  This is common in American English. Native speakers will pronounce unstressed syllables faster and at a lower pitch than stressed syllables.


Here is a close up of what OY looks like in an unstressed syllable, like in the word midpoint.


The stressed OY is in the top pictures, and the unstressed OY is in the bottom pictures. My mouth position looks very similar between the stressed and unstressed OY. But because the unstressed syllable is said faster and with a lower pitch, it will sound like it is unstressed. 

Practice Words and Sentences

Stressed OY. Boy.  Unstressed OY. Midpoint.


Here are some practice words and sentences:

Toy. OY. Toy.

I bought you a new toy.


Employer. OY. Employer.

My employer has a great benefit package.


Paranoid. Oy. Paranoid

Please don’t be paranoid about driving.


Point. OY. Point.

That was the point of the story.


Voice. OY. Voice.

Your voice is similar to your identity.


Oil. OY. Oil.

I need to change the oil in my car.


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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