Iwam language
      
May River Iwam, or just Iwam (cf. Sepik Iwam), is a language of Papua New Guinea.
Phonology
In non-final positions, /u/ /o/, /i/, and /e/ are [ʊ] [ɔ], [ɪ], and [ɛ], respectively.  /ə/ appears only in nonfinal syllables.  When adjacent to nasal consonants, vowels are nasalized; nasalization may also occur when adjacent to word boundaries.[3]
/p/ and /k/ are voiced fricatives ([β] and [ɣ]) respectively) when intervocalic and unreleased when final (/t/ is also unreleased when final).  /ŋ/ is a nasal flap ([ɾ̃]) word-initially and between vowels.  /s/ is [ts] initially and may otherwise be palatalized [sʲ].[3]  Sequences of any consonant and /w/ are neutralized before /u/ where an offglide is always heard.
Phonotactics
Bilabial and velar consonants and /n/ may be followed by /w/ when initial.  Other initial clusters include /pr/, /kr/, /hr/, /hw/, and /hn/ and final clusters are /w/ or /j/ followed by any consonant except for /h/ or /ŋ/.[3]
Notes
References
- Laycock, D.C. (1965). "Three Upper Sepik phonologies". Oceanic Linguistics (University of Hawai'i Press) 4 (1/2): 113–118. doi:10.2307/3622917. JSTOR 3622917. 
 
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  |  | Upper Sepik |  | 
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  |  | Middle Sepik |  | 
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  |  | Sepik Hill |  | 
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  |  | Others |  | 
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  |  | Official languages |  | 
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  |  Major Indigenous languages |  | 
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  |  Other Papuan languages |  | 
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