Iau phonology

The following discussion is based on Bateman (1990a).

## Consonants

Consonant phonemes of Iau

There are six consonants. /t d/ are dental; /s/ is alveolar. /b d/ are implosive, and may be realized as nasals [m], [n] before the low nasal vowel /a/ ([ã]). /d/ may also be realized as the liquid [l] before /a/.

/f/ is pronounced [ɸ]~[h] word-initially, or optionally as [x] before the high nonback vowels /i ɨ/. The labial allophone [ɸ] is preferred in the Foi dialect; the glottal allophone [h] is preferred in Turu. /f/ is always pronounced [h] word-medially and as an unreleased plosive [p̚] word-finally. /f/ is the only consonant that can occur word-finally, and occurs only in a limited number of words.

## Vowels

The low vowel is always nasalized, except when it is a component of a diphthong. The open-mid front vowel varies between [ɛ] and [æ].

The following diphthongs exist:

No diphthongs begin with /ɪ i i̝/ or end in /a ɔ/.

There are two triphthongs: /aui/ and /aʊɪ/. The back components of these triphthongs are realized as unrounded [ɯ] and [ɯ̽].

## Syllables

Syllables consist minimally of a vowel. They may include a single onset consonant and/or a single coda consonant. Diphthongs and triphthongs are attested. The template is (C)(V)V(V)(C). The tone-bearing unit is the syllable.

## Stress

Stress in Iau is predictable: it falls on the final syllable of disyllabic words. (Words may not be longer than two syllables.) The interaction between stress and tone is not clear.

## Tone

Iau is the most tonally complex Lakes Plain language. Unlike other Lakes Plain languages which can be disyllabic or trisyllabic, Iau word structure is predominantly monosyllabic. Iau has eight phonemic tones, transcribed by Bateman using numerical tone numbers (with 1 high and 5 low, as in much of Africa and America but the opposite of the convention used with Asian languages): two level tones (low and high), two rising tones (low rising and high rising), three falling tones (high-low, high-mid, and mid-low), and one falling-rising tone. Phonetically, these are:

* high 2 [˦]
* mid 3 [˧]
* high rising 21 [˦˥]
* low rising 43 [˨˧]
* high–low falling 24 [˦˨]
* high–mid falling 23 [˦˧]
* mid–low falling 34 [˧˨]
* falling–rising 243 [˦˨˧]

A sequence of two tones (called a tone cluster) may occur on one syllable. There are eleven tone clusters that can occur on verbs to mark aspect; only three of these can occur on nouns.

Some minimal sets in Iau illustrating phonemic tonal contrasts:

* be˧ 'fire'
* be˦˥ 'snake'
* be˨˧ 'path'
* be˦˨ 'thorn'
* be˦˧ 'flower'
* be˧˨ 'small eel'
* be˦˨˧ 'tree fern'

* te˧ 'mosquito'
* te˦˥ 'man'
* te˨˧ 'edible tuber'
* te˦˨ 'calf of leg'
* te˦˧ 'inlet of body of water'
* te˧˨ 'flooring'

Examples of monosyllabic words with the three 'compound' tones are /da˧˦˧/ 'mountain', /oi˦˥˧/ 'hand' and /sae˨˧˦˧/ 'knife'.

There is downdrift after low (3) and falling tones, and also of (24) following (243). A high-rising (21) tone rises slightly after another.

Tone is lexical on nouns, pronouns, numerals, prepositions and other parts of speech, but verbs are unmarked for tone. In verbs, each tone represents a different aspect or aktionsart. The complex system of aspectual marking via tone is discussed in Bateman (1986).

### Aspect

Iau also displays complex tonal verb morphology. Verbal roots do not have any inherent tone, but tone is used to mark aspect on verbs. Example paradigms:

### Mood

Tonal alternations can also serve as final mood and speech act particles.

* *tone 2*: speaker assumes the information is correct (such as rhetorical questions)
* *tone 34*: speaker asks a question to confirm what he believes is true (such as yes-no questions)
* *tone 23*: speaker is uncertain about the actual state of affairs

Example sentences:

(1)

'So the people from Bie killed father first?'
(2)

'Is the plane coming?'
(3)

'(I'm guessing) did you (pl) go by land?'