Keiner
In the sentence "keiner der Bälle ist grün", I do not understand why "keiner" is used. I understand that Ball is masculine and in that sentence is plural genitive, but I do not understand why "keiner" is in plural genitive.

Question

Answer

It isn't. In some cases the declination of a pronoun changes when it's not followed by a noun, and nom. sg. masc. is one of them.

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