Cases and functions

Case	Function	Question
Nominative	Subject of the sentence	кто? что?
Genitive	The 'of' case: Possession, Quantity & Negation	кого? чего?* чей?
Dative	The 'to/for' case: Indirect object, Recipient	кому? чему?
Accusative	Direct object	кого? что?
Instrumental	The 'by/with' case: Means of doing something	кем? чем?
Prepositional	The 'at/about' case: Location	о ком? о чём? где?

* - differentiated by context. Genitive is equivalent to the second case in English: the Possessive ('s)

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