Phonemic Alternatives

[s1] and [s2] are:

• Different phonemes /s1/ and /s2/ if

  • they occur in the same environments (overlap)

  and

  • make a difference in meaning (contrast)

  or
  
  

• Variants of a single phoneme /s/:

  • They are free variants if

  • they occur in the same environments (overlap)

  and

  • make no difference in meaning (don't contrast)

  
  or

  
  

  • They are allophonic variants if

  • they are in complementary distribution (mutually exclusive = they don't overlap)

  and

  • cannot make a difference in meaning (never contrast)

  Case 1:	[s1] is /s1/ and [s2] is /s2/
  Case 2:	[s1] and [s2] are /s/ plus rule