Have you ever encountered diphthongs? The answer is almost certainly yes, even if you didn’t realize it.
These delightful gliding vowels are so common in English that speaking without them would be nearly impossible. Diphthongs play a crucial role in distinguishing between words that would otherwise sound identical with just a single vowel sound (monophthong).
They add richness and fluidity to speech, making communication more dynamic and expressive.
What Is a Diphthong? In simple terms, a diphthong is a unique sound created by blending two vowel sounds within the same syllable. Unlike a single vowel sound, which remains constant, a diphthong involves a smooth, continuous transition from one vowel to another. This gives the sound a "gliding" quality, which is why diphthongs are often referred to as "gliding vowels."
The word "diphthong" comes from the Greek di (meaning "two") and phthongos (meaning "sound" or "voice"), highlighting the fact that two distinct vowel sounds are combined into one fluid sound. Importantly, both vowel sounds occur within the same syllable, which distinguishes diphthongs from instances where two vowel sounds belong to separate syllables, such as in "naive."
English contains eight primary diphthongs: /aɪ/ (as in "my"), /eɪ/ (as in "day"), /aʊ/ (as in "now"), /oʊ/ (as in "go"), /ɔɪ/ (as in "boy"), /ɪə/ (as in "beer"), /eə/ (as in "air"), and /ʊə/ (as in "tour"). Each diphthong begins with one vowel sound and glides smoothly into another, forming a single, elongated sound that enriches the flow of spoken English.
By learning to recognize and produce these diphthongs, you can better understand the rhythm and melody of English speech, which will ultimately enhance your communication skills.
Let's dive in!
1. /eɪ/ (as in "day") The /eɪ/ diphthong, also sometimes referred to as the "long A sound," is a vowel sound in English created by combining the /e/ (like the "e" in "bed") and /ɪ/ (like the short "i" in "pin").
Your mouth starts in the /e/ position with your lips slightly spread, before they close slightly and your tongue moves higher in your mouth as you transition to the /ɪ/ sound.
Examples of common words with the /eɪ/ diphthong include:
day - /deɪ/ say - /seɪ/ hey - /heɪ/ play - /pleɪ/ gray - /ɡreɪ/ cake - /keɪk/ make - /meɪk/ relate - /rɪˈleɪt/ eight - /eɪt/ 2. /aɪ/ (as in "my") Another of English's diphthong sounds, /aɪ/ can be expressed through various letter combinations, but the sound remains the same.
Non-native speakers often mistake the /aɪ/ diphthong for other vowel sounds like /ɪ/ or /ɑː/. Therefore, the word my (/maɪ/) might be incorrectly pronounced as me (/miː/).
These errors are sometimes so subtle that they appear insignificant to a non-native ear, but they greatly affect your accent. Thankfully, you can always do a quick speech evaluation on the BoldVoice accent app to catch and correct these errors.
To correctly pronounce the /aɪ/ sound, position your tongue low and back in your mouth, beginning with the /a/ sound. Then, quickly glide your tongue upwards and forward in your mouth, ending in the /ɪ/ position.
Your mouth should start open and relaxed, then smoothly close and bunch up slightly at the end. Below are some words that feature the /aɪ/ diphthong:
My - /maɪ/ Kite - /kaɪt/ Pie - /paɪ/ Like - /laɪk/ Ride - /raɪd/ High - /haɪ/ Aisle - /aɪl/ Cry - /kraɪ/ Eye: /aɪ/
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3. /ɔɪ/ (as in "boy") The /ɔɪ/ diphthong consists of the /ɔ/ sound, as in "thought," followed by the /ɪ/ sound, as in "sit." As with all English diphthongs, it is formed by seamlessly combining two simple vowels into one longer, gliding vowel sound.
The tongue starts in a mid-back rounded position and glides towards a near-high front unrounded position. The lips start rounded and become unrounded during the articulation of the diphthong.
Examples of words with this sound include:
Coin - /kɔɪn/ Boil - /bɔɪl/ Noise - /nɔɪz/ Choice - /tʃɔɪs/ Avoid - /əˈvɔɪd/ Spoil - /spɔɪl/ Employ - /ɪmˈplɔɪ/ Royal - /ˈrɔɪəl/ Annoy - /əˈnɔɪ/ 4. /aʊ/ (as in "now") The /aʊ/ diphthong is a complex vowel sound that occurs in many English words, such as "now," "cow," and "house."
This is one of the diphthongs in English that many non-native speakers struggle with in particular, because its specific sound combination may not exist in their dialect. Russian speakers, for example, may mispronounce the word “house” as “has” or “now” as "na.”
To pronounce this diphthong correctly, begin by opening your mouth wide as you form the /ɑ/ sound (like the "ah" in "father"). While maintaining the initial openness, smoothly glide your tongue and jaw upwards and backward until your mouth is partially closed, achieving the position for the /ʊ/ sound (like the "u" in "put").
/aʊ/ diphthong examples:
house: /haʊs/ loud: /laʊd/ cloud: /klaʊd/ shout: /ʃaʊt/ out: /aʊt/ down: /daʊn/ 5. /oʊ/ (as in "go") In American English , the /oʊ/ diphthong is a common and essential sound.
To pronounce the /oʊ/ sound like an American speaker, start with your tongue in the middle of your mouth and your lips rounded. Then, move your tongue slightly upward and close your lips a bit more to finish off the sound.
Examples of words with the /oʊ/ Diphthong:
go /ɡoʊ/ boat /boʊt/ home /hoʊm/ phone /foʊn/ low /loʊ/ toast /toʊst/ sew /soʊ/ 6. /ɪə/ (as in "beer") Now, an important distinction - diphthongs #6, #7, and #8 exist in English, however, they are mostly - or entirely - absent from the General American accent .
As you're surely aware, British and American English don't always sound the same - in fact, even the slang is different . These three diphthongs are some examples of the differentiation between English pronunciations across the continents.
Although these diphthongs are not common in the American accent, you likely will encounter them on your English journey nonetheless. Be careful to note when you're learning American pronunciations versus learning from British resources, as mixing the two together unintentionally could do more harm than good for your pronunciation in English.
The /ɪə/ diphthong is a vowel sound in British English that starts with the vowel sound /ɪ/ (as in "sit") and glides towards the schwa sound /ə/ (as in the second vowel in "sofa"). This sound is found in various words and can be a bit tricky for non-native speakers to master, particularly because of the schwa sound (/ə/).
Remember, American speakers don't add this schwa sound in this context. Instead, they simply pronounce the /ɪ/ vowel sound.
While British speakers might employ the /ɪə/ diphthong for words like "here," "near," and "beer," American speakers would opt for the single vowel sound /ɪ/.
7. /eə/ (as in "air") Once again, the /eə/ represents a distinction between American and British pronunciation. While British speakers commonly employ the /eə/ diphthong in everyday speech, Americans typically pronounce the simple vowel /e/ in its place.
This sound usually precedes the letter "r." Take the same /e/ vowel that begins our first diphthong, /eɪ/, and simply replace that second /ɪ/ vowel with an /r/ sound.
8. /ʊə/ (as in "tour") Again, this is one of our diphthong examples that highlights a difference between American and British pronunciation in English.
In cases where British speakers might employ the /ʊə/ diphthong, American speakers opt to utter simply /ʊ/ instead.
Remember, neither is correct nor incorrect - they're simply variations of the same language. As an English learner, however, it's important to recognize these distinctions in order to not overcomplicate English pronunciation and confuse yourself (and those around you, for that matter).
How to Master Diphthongs in English Listening Exercises and Minimal Pairs Practice One way to master diphthongs in English is by listening to native speakers and identifying the diphthongs and minimal pairs in their speech.
Minimal pairs are pairs of words that differ by only one sound. For example, "bit" (/bɪt/) and "bite" (/baɪt/). Listening to native speakers and practicing with minimal pairs can help you identify and produce diphthongs more accurately.
Recording and Playback Use a recording device to record yourself saying words with diphthongs. Play them back and compare your pronunciation with that of native speakers.
This self-assessment allows you to isolate and focus on specific diphthongs that you find challenging.
Use BoldVoice BoldVoice is an all-in-one AI-powered app that offers both listening exercises from real-life Hollywood coaches and practice features to help you master diphthongs. The platform also has a recording feature that leverages AI to produce instant, personalized feedback and help you track your progress over time.
If you’re looking to keep your learning organized and get all the help you need in one resource, then BoldVoice is the right place to get started.
Tongue Twisters Try tongue twisters that include diphthongs because they provide repetitive and challenging practice that enhances pronunciation, fluency, and confidence.
They make you articulate each sound clearly and help build muscle memory. For example, "The boy's toy boat floats" focuses on /ɔɪ/ and /oʊ/ diphthongs. Plus, it's fun!
Achieve Native-Level Pronunciation with English Diphthongs Diphthongs only account for a fragment of the core principles that make up good spoken English. However, they are a very important piece that cannot be sidelined. This is why you must take them seriously and master them in their entirety to harness fluency in your speech.
Pay attention to the accent of those around you, the target accent of your learning resources, and the accent that you hope to achieve in English.
BoldVoice is the hub to help you build speech confidence, boost self-esteem, and achieve flawless communication in the General American accent. Ready to take your English pronunciation to the next level? Sign up for BoldVoice to start your free 7-day trial today and see real improvement in your speech.
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