English Diphthongs
Learn how English gliding vowel sounds work and practise the main diphthongs used in British English pronunciation.
What Is a Diphthong?
The word diphthong comes from the Greek word diphthongos, meaning "two sounds".
In phonetics, a diphthong is a vowel sound in which the tongue moves from one vowel position towards another within the same syllable.
A diphthong is sometimes called a gliding vowel because the voice does not remain in one fixed position.
Compare this with a monophthong, where the vowel sound remains relatively stable.
For example, when you pronounce the word my, the sound begins around /a/ and moves towards /ɪ/.
This movement creates the diphthong: /aɪ/.
The 8 Traditional British English Diphthongs
Traditional descriptions of Received Pronunciation often identify eight main diphthongs.
Pronunciation changes over time and varies between accents, but these sounds are still very useful for learners studying British English pronunciation.
| IPA Symbol | Common Description | Example Words |
|---|---|---|
| /eɪ/ | The "A" sound | face, day, break |
| /aɪ/ | The "I" sound | price, high, type |
| /ɔɪ/ | The "OY" sound | choice, boy, voice |
| /aʊ/ | The "OW" sound | mouth, now, house |
| /əʊ/ | The "OH" sound | goat, show, no |
| /ɪə/ | The "EAR" sound | near, here, idea |
| /eə/ | The "AIR" sound | square, fair, there |
| /ʊə/ | The traditional "URE" sound | cure, pure, tour |
How Diphthongs Move
Diphthongs can be grouped according to the direction in which the tongue and mouth move during pronunciation.
Closing Diphthongs
The tongue moves towards a more closed or higher vowel position.
Examples include:
/eɪ/ /aɪ/ /ɔɪ/ /aʊ/ /əʊ/
Centering Diphthongs
In traditional British pronunciation, the tongue moves towards the central schwa sound /ə/.
Examples include:
/ɪə/ /eə/ /ʊə/
Why Are Diphthongs Important?
Diphthongs are important because English vowel sounds are not always pronounced as simple, fixed vowels.
Learners sometimes pronounce only the first part of the sound. This can make English pronunciation sound flat, clipped or influenced by the learner's first language.
Pronunciation tip: Do not try to pronounce two completely separate vowels. Think of the sound as one smooth movement from one position to another.
Practising English Diphthongs
A useful way to practise diphthongs is to exaggerate the movement slightly at first.
For example:
day - /deɪ/
my - /maɪ/
boy - /bɔɪ/
now - /naʊ/
go - /gəʊ/
Concentrate on the movement of the sound rather than trying to pronounce each IPA symbol separately.
Continue Learning English Pronunciation
Diphthongs are only one part of English pronunciation. You can also explore:
- English vowel sounds
- English consonant sounds
- Minimal pairs
- Word stress
- Sentence stress and rhythm
- Connected speech
- English intonation
- The schwa sound /ə/