Vowels 9 and 12, /u/ versus /ə/    15 pairs
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Since the schwa has to be unstressed while /u/ is likely to be prominent, very few pairs were found in the dictionary. I have included several involving the weak forms but, cos, from, to and was which are of doubtful status since they cannot occur in isolation. 
babu barber
  babus barbers
bayou buyer
  bayous buyers
boot but
coos cos
cuckoo cooker
  cuckoos cookers 
Frome from
seafood Seaford   
two to
too to
whom h'm 	
woos was

John Higgins, Shaftesbury, December 2009
updated Chiang Mai, 2025