Which and whose (какой, чей)

Asking "Whose" (Чей)

To ask who owns something, use the question word чей (whose). Because it modifies the noun in the sentence, it behaves like an adjective and changes its ending to match the noun's gender.

GenderForm
Masculineчей
Feminineчья
Neuterчьё

Use the masculine form чей with masculine nouns like карандаш (pencil) and ключ (key):

Whose pencil is this?
Чей это карандаш?
This is my pencil, but whose key is this?
Это мой карандаш, а чей это ключ?

For a feminine noun like ручка (pen), use чья:

Whose pen is this?
Чья это ручка?

Asking "Which" or "What kind" (Какой)

To ask for specific details about an object—such as "which one", "what kind", or "what color"—use какой. This word also changes to agree with the gender of the noun.

GenderForm
Masculineкакой
Feminineкакая
Neuterкакое

For masculine nouns like цвет (color), use какой:

What color is this?
Какой это цвет?

For feminine nouns, use какая:

What kind of dog is this?
Какая это собака?

Answering with Adjectives

When answering these questions, any adjectives in your response must also match the noun's gender. Notice how a neuter noun like пальто (coat) requires the neuter ending -ое on all of its describing words:

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