than the unstressed vowel. That can be analyzed as light syllables changing to heavy under stress: {| cellspacing="6" style="line-height: 1.1em;" |- style="vertical-align: top;" | (L'L)L(qayá:)ni || → || (L'H)L[qayá:ni][(qa.yá:).ni] || "in another's kayak" |- style="vertical-align: top;" | (L'L)('H)Lsaguyá:ni || → || (L'H)('H)L[sagú:yá:ni][(sa.gú:).(yá:).ni] || "in another's drum" |} Both Central Siberian and Central Alaskan Yup'ik show this iambic lengthening of light syllables. When the stressed syllable is underlyingly heavy (such as LHL)), there is dialectal variation. The Chaplinski variety of Central Siberian Yupik shows no extra lengthening of the already long vowel: the heavy syllables remain heavy (no change). The St. Lawrence variety of Central Siberian Yupik has further iambic overlengthening, resulting in a change from underlying heavy to a phonetically superheavy syllable (S). In those cases, Central Alaskan Yup'ik changes the first light syllable in what would be a (LH) foot to a heavy syllable which then receives stress. The light to heavy shift is realized as consonant gemination (of the onset) in CV syllables and as consonantal lengthening of the coda in CVC syllables: Note that in the Chaplinski variety because of iambic lengthening there is a neutralization of vowel length contrast in nonfinal stressed syllables. Morphology The Yupik languages, like other Eskimo–Aleut languages, represent a particular type of agglutinative language called an affixally polysynthetic language. Yupik languages "synthesize" a single root at the beginning of every word with various grammatical suffixes to create long words with sentence-like meanings. Within the vocabulary of Yupik there are lexical roots and suffixes that can be combined to create meanings that in most languages are expressed by multiple free morphemes. Although every Yupik word contains one and only one root that is rigidly constrained to word-initial position, the ordering of the suffixes that follow can be varied to communicate different meanings, principally through recursion. The only exception lies with case suffixes on nouns and person suffixes on verbs, which are restricted to the end of the words in which they occur. Yupik is an ergative language both in nominal and verbal morphology. It has obligatory polyagreement on all verbs with subject and object but not with the theme of a ditransitive verb. Writing systems The Yupik languages were not written until the arrival of Europeans around the beginning of the 19th century. The earliest efforts at writing Yupik were those of missionaries who, with their Yupik-speaking assistants, translated the Bible and other