Lips
Mouth slightly open, lips fully neutral. No rounding, no spreading. Keep them still for the entire sound.
The vowel in "nurse". A long, steady central sound with no "r" (in British English).
Example words: nurse, bird, her, word, learn

Mouth slightly open, lips fully neutral. No rounding, no spreading. Keep them still for the entire sound.
Tongue sits mid-central, held even and level. Crucially, in British English it does not curl back for an "r". It stays flat and steady.
Long. Hold it steadily: "her" and "bird" carry a full, sustained vowel. It's like a long, stressed version of the schwa.
Record "bird". Listen for any r-coloring at the end. In a British model the vowel should sound identical from start to finish, like a long hum with the mouth slightly open. If you hear the sound change partway, your tongue moved.
The spelling shows "ur", "ir", or "er", which tempts you to curl the tongue and say an "r". In British English there is no "r" sound here at all, just a long pure vowel. The other trap is letting the vowel drift toward "eh" or "oh". It must stay dead center, with nothing moving.
🔊 plays the app's native voice. 🎤 records you so you can play it back next to it. Your recording stays in your browser.