Finnic Genitives and Accusatives
Finnic languages (Finnish, Estonian) have genitive cases.
In Finnish, prototypically the genitive is marked with -n, e.g. maa – maan "country – of the country". The stem may change, however, with consonant gradation and other reasons. For example, in certain words ending in consonants, -e- is added, e.g. mies – miehen, and in some, but not all words ending in -i, the -i is changed to an -e-, to give -en, e.g. lumi – lumen "snow – of the snow". The genitive is used extensively, with animate and inanimate possessors. In addition to the genitive, there is also a partitive case (marked -ta/-tä or -a/-ä) used for expressing that something is a part of a larger mass, e.g. joukko miehiä "a group of men".
In Estonian, the genitive marker -n has elided with respect to Finnish. Thus, the genitive always ends with a vowel, and the singular genitive is sometimes (in a subset of words ending with a vocal in nominative) identical in form to nominative.
In Finnish, in addition to the uses mentioned above, there is a construct where the genitive is used to mark a surname. For example, Juhani Virtanen can be also expressed Virtasen Juhani ("Juhani of the Virtanens").
A complication in Finnic languages is that the accusative case -(e)n is homophonic to the genitive case. This case does not indicate possession, but is a syntactic marker for the object, additionally indicating that the action is telic (completed). In Estonian, it is often said that only a "genitive" exists. However, the cases have completely different functions, and the form of the accusative has developed from *-(e)m. (The same sound change has developed into a synchronic mutation of a final m into n in Finnish, e.g. genitive sydämen vs. nominative sydän.) This homophony has exceptions in Finnish, where a separate accusative -(e)t is found in pronouns, e.g. kenet "who (telic object)", vs. kenen "whose".
A difference is also observed in some of the related Sámi languages, where the pronouns and the plural of nouns in the genitive and accusative are easily distinguishable from each other, e.g., kuä'cǩǩmi "eagles' (genitive plural)" and kuä'cǩǩmid "eagles (accusative plural)" in Skolt Sami.
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