Stressed r-coloured vowel · er / ir / ur The tip curls toward the ridge but never touches it, and the tongue body is concave — exactly the /r/ gesture. The difficulty was never the vowel but this curl-without-contact.
Three steps to /ɝ/
Curl first, then keep the gap.
Tip up and back, touching nothing
The tip rises toward the back of the ridge with a visible gap to the palate. That gap is the whole point — draw it as contact and you have a trill or a /d/.
Hollow the tongue body
While curling, the middle of the tongue drops into a groove (visible in the drawing). That is the signature shape of American /r/.
Self-check: hold it for two seconds
Sustain the /ɝ/ of bird for two seconds. If the tip is touching anything you cannot hold it — contact forces a release. Holding without contact is the test.
Articulation (side view)
One speaker, one instant: tongue position and lip shape only. The amber circle marks what to look at; the caption says how it differs from the sound it is usually confused with.
Spelling: er, ir, ur and or
Four spellings, one sound — and or after w is the one everybody misses.
Stressed er is /ɝ/ (person /ˈpɝːsn/). ★ Unstressed it becomes /ɚ/ (teacher) — that is a different page.
Very stable: bird, first, girl, shirt, third.
Also stable: turn, nurse, hurt, burn, purse.
★ The big one: or after w is /ɝ/ (work /wɝːk/, word /wɝːd/, world /wɝːld/), while other or is /ɔr/ (fork /fɔrk/). Look at the preceding letter.
Why learners replace /ɝ/
The nearest L1 rhotic curls at a different place.
No curl at all
bird → /bɜːd/, work → /wɜːk/. Without the curl the word is a different word to a native listener.
The main error on this page. Test: the tongue body hollows and the tip lifts — you can feel the tip move from outside the jaw.
Curl too hard, trill
The tip presses the ridge and flaps, producing a trill. English /ɝ/ never makes contact.
The gap in the drawing is the test: hold it two seconds without touching and there is no contact.
or after w read as /ɔr/
work → /wɔrk/, word → /wɔrd/, by analogy with the usual or.
Per word: work, word, world, worse, worth take /ɝ/.
Word list
27 words grouped by where the sound sits in the word. Click a word to hear it. These are recorded as separate words, not cut out of the sentences above — a word cut from a sentence carries its neighbours' transitions and always sounds muddier. All three groups use the same speaker, so what changes between them is position, not voice.
Word-initial9
Word-medial9
Word-final9
Three groups of nine. In the final group (her, fir, fur, stir, blur, occur, refer, prefer, transfer) the r is the only audible part — and the first thing learners drop.
Corpus and acoustic measurements
Click any word in a sentence to play from that word. The pale band over the waveform marks the measured boundary of the target word.
Per-token data
Every number below is measured directly from the audio, not hand-annotated.
| Token | Accent | Sex | Target | Word length | ɝ duration | F0 | Pitch range | HNR |
|---|
Where the numbers come from
Every figure on this page can be recomputed from the description below.
Corpus: 12 English sentences synthesised with four American voices (two male, two female), each containing one target word, covering initial, medial and final positions. Audio is 22.05 kHz mono 64 kbps; each clip runs from 1.2 s before to 1.5 s after the target word.
Word boundaries: taken from the engine's word-level timestamps (WordBoundary) and corrected for the fixed offset between the engine timeline and the audio start (estimated per item). The target word is shaded in the waveform.
Phoneme boundaries: measured by forced alignment with the MMS_FA acoustic model. Each character's aligned frame range is kept, then a dynamic program maps the character sequence onto the phoneme sequence (th→θ, ng→ŋ, ck→k). Boundaries fall in the middle of the transition between characters; within-word coverage is 100%. Time precision is the model frame length, 20 ms, and boundaries are taken at midpoints, so effective resolution is about 10 ms.
Pitch: Praat's autocorrelation (to_pitch), 10 ms frame step, search range narrowed to the speaker's estimated range, octave errors removed. «Pitch range» is max minus min F0 within the word.
Why there are no paired differences here: this is a single-phoneme page. Eight other pages are contrast pages (θ/ð, l/r/n, vowel length) where the numbers come from paired words read by one speaker. A single-phoneme page has nothing to compare against — pairing it with a neighbour would measure that neighbour, which belongs to a different page.