Understanding how to pronounce the diphthongs in English is one of the most practical things you can do for your spoken clarity. A diphthong is not a complicated idea: it is simply a vowel sound that moves. Your mouth starts in one position and glides to another, all within a single syllable. The word "price" contains one. So do "face", "choice", and "mouth". Get the movement right and these words land cleanly. Hold the vowel still — as many learners do — and the word can blur into something else entirely.
This article covers all eight diphthongs in standard English, tells you where each one starts and ends, and gives you a sentence you can say aloud to practise each one. It also flags the mistakes that appear most often, so you know what to listen for in your own speech.
What makes a diphthong different from a regular vowel
Most vowel sounds are monophthongs — the mouth holds a single position for the duration of the sound. The short vowel in "sit" stays put. So does the vowel in "hot". A diphthong does something different: it begins at one vowel position and moves — glides — toward another. That movement is the sound. If you remove it, you have a different vowel, which means a different word.
English has eight diphthongs. Linguists group them loosely by where the glide ends up: sounds that move toward the /ɪ/ position (as in "kit"), sounds that move toward the /ʊ/ position (as in "foot"), and sounds that move toward the schwa /ə/. This grouping is not something you need to memorise, but it is useful to know that a direction is always involved.
The eight diphthongs, one by one
/eɪ/ — the vowel in "face"
Start with a mid-front vowel, close to a short "e", then glide upward toward /ɪ/. The words "late", "rain", "they", and "eight" all use this sound despite the different spellings.
Practise this sentence: "They came late on the same train."
Common mistake: flattening it to a pure /eː/. The result sounds clipped and can make "lane" sound more like the vowel in "len".
/aɪ/ — the vowel in "price"
This is a wide glide. Start from an open, low position — roughly the vowel in "father" — and move up to /ɪ/. It appears in "like", "night", "my", "buy", and "aisle".
Practise this sentence: "I might try to find the right file tonight."
Common mistake: starting too high, so the glide shortens and "five" sounds like "fev" or a flat /aː/.
/ɔɪ/ — the vowel in "choice"
Begin with a rounded, mid-back vowel (close to the vowel in "thought") and glide forward and upward to /ɪ/. This one appears in "boy", "noise", "coin", "enjoy", and "loyal".
Practise this sentence: "The boy made a noise with a coin."
Common mistake: replacing it with a pure /oː/, which makes "oil" sound like "all".
/əʊ/ — the vowel in "goat" (British English)
Begin from a central, unstressed position — the schwa — and glide back and upward to /ʊ/. You hear this in "go", "home", "road", "know", and "though". Note that in many American accents, this diphthong starts slightly differently, closer to /o/, but the glide toward /ʊ/ remains.
Practise this sentence: "She drove home alone on the old road."
Common mistake: holding a pure /oː/ throughout, which flattens the word and can make "goat" sound like a very different vowel to native listeners.
/aʊ/ — the vowel in "mouth"
Start low and open, then glide up and back to /ʊ/. This sound lives in "now", "found", "town", "loud", and "how".
Practise this sentence: "The crowd found the sound too loud."
Common mistake: starting too far back in the mouth, so "town" sounds closer to "torn". The start position should feel similar to the /aɪ/ diphthong — open and forward.
/ɪə/ — the vowel in "near"
Begin at the /ɪ/ position (as in "sit") and glide toward the schwa. This appears in "here", "ear", "real", "idea", and "fear". In many contemporary British accents, this diphthong is increasingly smoothed to a long /ɛː/, but the traditional glide remains common and is well worth knowing.
Practise this sentence: "I fear the idea isn't clear from here."
Common mistake: replacing it with a pure /iː/, so "hear" sounds like "he". The schwa at the end gives the word its characteristic warmth.
/eə/ — the vowel in "square"
Start at a mid-front position, similar to the vowel in "dress", and glide toward the schwa. It appears in "there", "care", "air", "wear", and "where".
Practise this sentence: "Take care — there's a rare pair of bears over there."
Common mistake: this diphthong is often pronounced as a pure long vowel /ɛː/ by native speakers too, so variation is normal. What matters is not confusing it with /ɪə/: "here" and "hair" are different words.
/ʊə/ — the vowel in "cure"
Begin at the /ʊ/ position (as in "foot") and glide toward the schwa. This diphthong is retreating from many accents — words like "sure" and "pure" are increasingly said with /ɔː/ rather than /ʊə/ — but it remains useful in words like "lure", "during", and "tourism".
Practise this sentence: "I'm sure the tour was pure luxury."
Common mistake: using /ɔː/ throughout, which is increasingly acceptable, but worth knowing as a distinction in formal or careful speech.
Why the glide matters so much
The most consistent error learners make with diphthongs is not mispronouncing the start vowel or the end vowel — it is failing to complete the journey between them. Under the pressure of normal speaking speed, the glide compresses and then disappears. This matters because English words are often distinguished by their diphthong alone. "Fail" versus "fell". "Coil" versus "call". "Loud" versus "lard". If the movement stops, so does the distinction.
One useful exercise: say the two component vowels separately, then blend them into a single smooth movement, then place that movement inside the word. For /aɪ/, say /a/ — /ɪ/ — /aɪ/ — "light". Repeat until the glide feels automatic, then use the word in a sentence at normal speed.
Recording yourself matters here. Most people cannot hear their own missing glides in real time — the brain fills in what it expects to say. Playing back a recording removes that expectation. If you want feedback that goes beyond your own ear, how ummute works is worth a look.
A note on spelling
English spelling is not a reliable guide to diphthongs. The /eɪ/ sound appears in "face", "rain", "they", "weigh", "break", and "eight" — six different spelling patterns for one sound. Rather than learning lists of spellings, learn to recognise the sound itself, and to produce it correctly. Spelling will follow with reading practice; pronunciation needs its own work.
If you are building a wider picture of how your spoken English is landing with listeners, the benefits of focused pronunciation work are worth understanding before you begin.
Bringing it together
Diphthongs reward patient, physical practice. They are movements, not positions, and the only way to own a movement is to repeat it slowly, correctly, and often enough that it becomes automatic. Work through the eight, give the ones that feel unfamiliar more time, and use real sentences — not isolated sounds — as your main practice material. The goal is not to sound like someone else. It is to be clearly understood as yourself.