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CaseSingularPlural
Nominativeименительный · кто? что?начальник начальники the subject: who or what acts
Accusativeвинительный · кого? что?начальника начальников the direct object of the verb
Genitiveродительный · кого? чего?начальника начальников possession, absence, "of"-phrases
Dativeдательный · кому? чему?начальнику начальникам the receiver: to or for someone
Instrumentalтворительный · кем? чем?начальником начальниками the tool or companion: with, by
Prepositionalпредложный · о ком? о чём?начальнике начальниках location and topics: in, at, about

Начальник is animate, so its accusative copies the genitive: the form after "I see..." matches the form after "of".

Look up any other word in the Russian declension tool, see where начальник ranks in the most common Russian words, or start from Russian cases explained if the table above is new territory. More vocabulary lives in Russian words by topic and Russian phrases.

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