Sámi do not: There is a maximally three-way contrast among open vowels between , and , both short and long. The vowel spelled is in stressed syllables, in unstressed syllables. The vowel spelled is in stressed syllables if the next syllable has a back vowel (including but not ), and everywhere else (including all unstressed syllables). In other eastern varieties, only a two-way contrast between and is found. Jarvansalo (2006) reports the Kárášjohka dialect following this contrast, but having for , for stressed . There is a length contrast between short and long diphthongs. In other dialects, this distinction exists as well, but is allophonic. Some Torne dialects have and instead of stressed and (from diphthong simplification) as well as unstressed and . Phonological processes Diphthong simplification Diphthong simplification, also known as umlaut, is a process whereby a diphthong loses its second component and becomes a long monophthong: ie → ī: viehkat "to run" → vīhken "I ran" ea → ē: geassi "summer" → gēsiid "of the summers" oa → ō: goarrut "to sew" → gōrro! "sew!" uo → ū: muorra "tree" → mūrrii "into the tree" Historically, diphthong simplification was caused by a short i or u in the following syllable, the same conditioning that still exists in neighbouring Lule Sámi. In Northern Sámi, these vowels have now become short and , except when followed by , so simplification can occur when the next syllable contains or , or the sequences or . The process is complicated by two factors. Firstly, vowel length is not indicated in the spelling, so it's not possible to tell whether the first vowel in ui is short or long. It is short in the illative singular and thus causes simplification (viessu "house" → vīssui "into the house"), but it is long in the plural forms and does not cause any simplification (viessūide "into the houses"). A second complicating factor is that under some circumstances, original long i and u in unstressed syllables have shortened to e and o (denoted in grammars and dictionaries with an underdot ẹ and ọ to distinguish them). These shortened vowels do not cause simplification, but are indistinguishable from the older originally short vowels that do trigger it. These cases must simply be memorised. Unstressed vowel shortening Shortening of long vowels in unstressed syllables occurs irregularly. It commonly occurs in the first element of a compound word, in a