The Nias language is an Austronesian language spoken on Nias Island and the Batu Islands off the west coast of Sumatra in Indonesia. It is known as Li Niha by its native speakers. It belongs to the Northwest Sumatra–Barrier Islands subgroup which also includes Mentawai and the Batak languages. It had about 770,000 speakers in 2000. There are three main dialects: northern, central and southern. It is an open-syllable language, which means there are no syllable-final consonants. Dialects Nias is typically considered to have three dialects. Northern dialect: particularly the Gunungsitoli variety, Alasa and Lahewa area. South dialect: South Nias, Gomo Area, Telukdalam Area and Batu Islands. Central dialect: West Nias, particularly in Sirombu and Mandrehe areas. Cognate percentage among the dialects of Nias is about 80%. The northern variant is considered the prestige dialect. The only complete Bible translation is written in the northern dialect and is used by speakers of all dialects. Phonology Nias has the following phonemes (sounds only found in the northern dialect are given in , southern-only sounds are in ): Phonetic descriptions of the sounds traditionally written as and greatly vary. Sundermann (1913) and Halawa et al. (1983) describe them as prenasalized stop and prenasalized trilled stop for the northern dialect, while Brown (2005) records them as trill and trilled stop for the southern dialect. In an acoustic study of Nias dialects from three locations, Yoder (2010) shows a complex pattern of four phonetic realizations of and : plain stop, prenasalized stop, stop with trilled release, stop with fricated release. The status of initial is not determined; there are no phonetic vowel-initial words in Nias. The contrast between and (both written in common spelling) is only observed in the southern dialect. Here, the fricative only occurs in initial position in the mutated form (see §Noun case marking (mutation)) of nouns beginning with f, e.g. ~ . The approximant can appear in initial and medial position, and is in free variation with for many speakers of the southern dialect. For the northern dialect, only fricative approximant is reported, corresponding to both sounds of southern Nias. The semivowel is a distinct phoneme and is written in common spelling. Grammar Nias has an ergative–absolutive alignment. It is the only known ergative–absolutive language in the world that has a "marked absolutive", which means that absolutive case is marked, whereas ergative case is unmarked. There are no adjectives in