Vowels 17 and 20, // versus /ʊə/    12 pairs      [bowboor.html]

The // diphthong is spelled <ou> or <ow>. The /ʊə/ diphthong is spelled <ure> or <oor>.

This is a contrast between two diphthongs with different starting positions and direction of movement. It is not a problem for learners.

The density figure is 1.14%. The set makes 6 semantic contrasts giving a loading of 55%.

aloud allured
allow allure
  allowed allured
  allows allures
bough boor
  boughs boors
bow boor
  bows boors 
loud lured
mow moor
  mows moors 
spouse spoors

John Higgins, Shaftesbury, December 2009