Case marking

Case is a special grammatical category whose value reflects the grammatical function performed by a noun, pronoun, adjective, participle or numeral in a phrase, clause, or sentence. In some languages, nouns, pronouns, adjectives, determiners, participles, prepositions, numerals, articles and their modifiers take different inflected forms depending on what case they are in. English has largely lost its case system, although it still has 3 cases that are simplified forms of nominative case, accusative case and genitive case: subjective case (I, you, he, she, it, we, they, who, whoever), objective case (me, you, him, her, it, us, them, whom, whomever) and possessive case (your, yours, my, mine, his, hers, its, their, theirs, our, ours, whose, whose ever). Distinctions can be seen with the personal pronouns: forms such as I, he and we are used in the role of subject ("I kicked the ball"), whereas forms such as me, him and us are used in the role of object ("John kicked me").

Languages such as Sanskrit, Ancient Greek, Latin, Armenian, Hungarian, Tibetan, Turkish, Tamil, Russian, Polish, Serbo-Croatian, Estonian, Finnish, Icelandic, Ukrainian, Lithuanian, Basque, Esperanto and the majority of Caucasian languages have extensive case systems, with nouns, pronouns, adjectives, and determiners all inflecting (usually by means of different suffixes) to indicate their case. A language may have a number of different cases (German and Icelandic have four; Turkish, Latin and Russian each have at least six; Armenian, Polish, Serbian, Croatian, Ukrainian, and Lithuanian have seven; Sanskrit has eight; Estonian and Finnish have fifteen, Hungarian has eighteen and Tsez has sixty-four). Commonly encountered cases include nominative, accusative, dative, and genitive. A role that one of these languages marks by case will often be marked in English using a preposition. For example, the English prepositional phrase with (his) foot (as in "John kicked the ball with his foot") might be rendered in Russian using a single noun in the instrumental case, or in Ancient Greek as τῷ ποδί (tōî podí, meaning "the foot") with both words (the definite article, and the noun πούς (poús) "foot") changing to dative form.

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