Russian declension

In the Russian language, the system of grammatical declension is elaborate and complex. Nouns, pronouns, adjectives, demonstratives, most numerals and other particles are declined for two grammatical numbers (singular and plural), three grammatical genders (masculine, feminine and neuter) and six grammatical cases (see below). This gives dozens of spelling combinations for most of the words, which is needed for grammatical agreement within and (often) outside the proposition. Also, there are several paradigms for each declension with numerous irregular forms.

Russian is relatively conservative in its declensions compared to many other modern Indo-European languages (English, for example, has almost no declensions remaining in the language). The complexity of its declensions resembles older languages such as Latin and Ancient Greek than most modern languages.

Nominal declension is subject to six cases – nominative, genitive, dative, accusative, instrumental, and prepositional – in two numbers (singular and plural), and absolutely obeying grammatical gender (masculine, feminine, and neuter). Up to ten additional cases are identified in linguistics textbooks, although all of them are either incomplete (do not apply to all nouns) or degenerate (appear identical to one of the six simple cases). The most recognized additional cases are locative (в лесу, в крови, в слезах), partitive (чаю, сахару, коньяку), and several forms of vocative (Господи, Боже, отче). The adjectives, pronouns, and the first two cardinal numbers further vary by gender. Old Russian also had a third number, the dual, but it has been lost except for its use in the nominative and accusative cases with the numbers two, three and four (e.g. два стула [dvɐ ˈstulə], "two chairs", now reanalyzed as genitive singular).

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