UI

This letter combination is typically formed as either úi or ui.

1. As úi, it represents /uɪ/:
to ruin, the ruin -> ta rúine, þe rúin

2. As ui, it can represent /wi/ or /wɪ/:
to sweep -> ta suipe
to swing -> ta suingue
twit -> tuit
to tweet; the tweet, tweets (of a bird) -> ta tuite; þe tuite, tuíts
suite
swift -> suift
swiss -> suiss
Swedish -> Suídish

3. See "silent u" under U