The /e/ vowel is spelled <e> throughout. The diphthong /ʊə/ is spelled <our>, <oor> or <ur> in jury. The pair congress/congruous is of doubtful status since congruous would normally be perceived as a three-syllable word in which /ʊə/ is two vowels and not a diphthong. This dictionary gives /bʊən/ as the preferred pronunciation of bourne, though another common pronunciation is /bɔn/.
This is a contrast bewteen a short front vowel and a back centring diphthong, and is no rpblem for any learner.
The mean density is low at 0.2%. The pairs make 9 semantic contrasts, giving a high loading of 82%.
ben bourn bens bournes Bess bourse congress congruous Delhi dourly jerry jury jerries juries lead lured Les lures Med moored Ted toured
John Higgins, Shaftesbury, January 2011