We have other vowel combinations which aren't surprising in sound.
'aa' is now spelled and pronounced á. 'oo' is now spelled and pronounced ó. 'uu' is now spelled and
pronounced ú. 'ee' is now spelled and pronounced é. 'ii' is now spelled and pronounced í.
We don't really use au, eu (which has been almost entirely replaced by éa), ie, iu, oa, ou, oe, ue, uo, in
So that leaves 'io', 'oi' and 'ui.'
Pronunciation Of The Other Vowel Combinations
This is very simple. You can pronounce either letter. It's your call.
In other words, 'io' is a short 'i' or a short 'o' - you get to decide.
Similarly, 'oi' is a short 'o' or a short 'i' - you get to decide.
As for 'ui', the same applies. You can say it as a short 'u' or as a short 'i' - your call.
There are some dialectal variations on these, but for now, just make your choice and you'll be well
understood. Click below to hear these. Memorize them.
Here's a summary of pronunciation for io, oi, and ui:
io short i or short o - your call
oi short o or short i - your call
ui short u or short i - your call
Both Ó Coinn and Ó Cuinn in Irish give us "O'Quinn" in English.