This is the ɔɪ sound, as in the words:
- point /pɔɪnt/
- boy /bɔɪ/
- voice /vɔɪs/
Diphthongs sounds are a combination of two vowel sounds that are pronounced within the same syllable.
The ɔɪ sound is a combination of /ɔ:/ and /ɪ/ or /i:/. Like vowels the diphthongs are all made through the mouth and are voiced which means that you vibrate you vocal chords to make the sound.
Unlike with vowels and consonants, when you pronounce a diphthong sound, your mouth will change position and shape as you say the sound, because they combine two vowel sounds.
So as you say the ɔɪ sound your mouth will start on the position of the /ɔ:/ sound and finish on the position of the /ɪ/ or /i:/ sound.
How the ɔɪ sound is spelled
One of the most difficult things about learning English is the spelling. This is because spelling is often not phonetic especially the vowels and diphthongs. So you will find the /ɔɪ/ sound spelled many different ways. But it is often spelled with the letters “o-I” or “o-y”, as in the words:
- join /dʒɔɪn/
- oil /ɔɪl/
- choice /tʆɔɪs/
- enjoy /ɪnˈdʒɔɪ/
The ɔɪ sound is not very common but there are a couple more example you should know, they are:
- avoid /әˈvɔɪd/
- employee /ɪmˈplɔɪiː/