English-related creole language Tok Pisin. The influence of English is increasing, though, as English has been implemented in the school curricula. Teachers have to gradually introduce it up to the 3rd grade and from then on it is supposed to be the main language in teaching. Tok Pisin is the official language in the northern mainland region and consequently used by the Duna to communicate with the outside. The ability to speak Tok Pisin varies, with some only being able to passively understand Tok Pisin and others, mainly people having spent time outside of the Duna community, being fluent. The general status of Tok Pisin led to first variations, meaning Tok Pisin-derived words can be used next to Duna equivalents, f.e. people say siriki, meaning "to trick", instead of the Duna verb adjunct ho with the same meaning. The close contact with the Huli people has had the most influence on the Duna language to the extent that Duna speakers make a clear distinction between the Duna spoken in the north-western region and the one spoken in the south-eastern region, which is closest to the Huli area. The influence can be observed in phonetic and lexical variation. For example, many of the synonym sets of Duna have one variant that is likely derived from Huli words, seen by the similarity to its Huli counterpart: yu and ipa both mean "water, liquid" where /ipa/ is also a Huli word. Phonology In Duna phonology, the syllable structure is generally , which means that the coda is always empty. Occupation of the onset is optional, though consonant clusters are not allowed. This is why loanwords that originated from words with consonant clusters as in factory have adjusted to the Duna syllable structure by inserting vowels between consonants. Consonants Duna's consonant system consists of twenty consonant phonemes with some allophonic variation. Stop phonemes are distinguished by aspiration and voicing / prenasalisation in three places of articulation. Only the glottal fricatives appear as distinct phonemes, but the aspirated stops can be realized as allophonic affricates or fricatives word-initially, f.e. in /pʰu/ "blow" which occurs as voiceless stop [pʰu], affricate [pɸu] or fricative [ɸu]. The glottal fricative only appears at the beginning of roots and alternates between a voiceless [h] and a murmured [ɦ] realisation: see /hɔ/ "here it is" with [hɔ] or [ɦɔ]. Allophonic variation also occurs with word-initial prenasalised stops in bilabial or velar