Pronounce English Accurately

Vowel 18 - The diphthong /ɔɪ/

Video Text

Vowel 18: Diphthong /ɔɪ/

/ɔɪ/ in the sound in 'toy' and 'boy'.

The tongue starts in the position for /ɔː/, with the lips rounded, and glides towards the position for the vowel /iː/. This results in a very clear, wide diphthong which is usually easy to recognise and make and which occurs in many languages.

It's not normally a problem, except for spellings which look like /ɔɪ/ but aren't.

The two possible spellings are 'oy' at the end of a word and 'oi' in the middle.

Examples are 'boy', 'boil', 'noise', 'moist', 'toy', 'oil', 'toil', 'soy', 'soya', 'foil', etc..

In British English, 'buoy' is a homophone of 'boy' and 'buoyant' also has no sound for the letter 'u'. In American English 'buoy' can be either /bɔɪ/ or /buːi/. /ˈbɔɪ.ənt/

Not all words which look like they should have /ɔɪ/ in them actually do.

Which of these words do NOT have the /ɔɪ/ sound;

1. coin 2. choir 3. alloy 4. coincide 5. abbatoir 6. tortoise

The answers are 'choir' /ˈkwaɪ.ə/, 'coincide'/kəʊ.ɪnˈsaɪd/, 'abbatoir' /ˈæb.ət.wɑː/ and 'tortoise' /ˈtɔː.təs/, which in RP is homophonous with 'taught us'!

You will hear /ˈtɔː.tɔɪs/ but it is not regarded as correct.

Examples of /ɔɪ/:

All the boys sat up in the joists noisily playing with toys.

Those loyal to the royals joined in joyfully. The others boycotted the appointment.

Next Lesson: Vowel 19 - The Diphthong /əʊ/

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