The /ʊ/ vowel is usually spelled <oo>, <u>, and <oul> should.The /aɪ/ vowel is spelled <iCe> or <igh>, and turns up as <ei> in the loan word Reich. The computer picked out three more minmal pair sets arising from the contrast of /ʊə/ with the triphthong /aɪə/, namely bourse/bias, moor/mire and tour/tire. I have taken these out of the list since /ʊ/ and /ʊə/ are normally regarded as distinct phonemes.
This is a contrast between a short vowel and a diphthong, fairly well separated in the mouth. There is very little likelihood of confusion.
Interesting pairs include:
The density figure is 2.55%. The set makes 22 semantic contrasts giving a loading of 44%.
book bike booked biked booking biking books bikes bull bile foot fight footing fighting foots fights footer fighter footers fighters full file good guide goods guides hood hide hooding hiding hoods hides hook hike hooked hiked hooking hiking hooks hikes hookah hiker hookahs hikers hooker hiker hookers hikers look like looked liked looking liking looks likes pud pied pull pile pulled piled pulling piling pulls piles pull-up pile-up pull-ups pile-ups rook Reich rooks Reichs should shied soot cite sooted cited sooting citing soots cites took tike wood wide wooden widen wool while wools whiles woolly wily woolier wilier wooliest wiliest
John Higgins, Shaftesbury, December 2009