Russian grammar - The Nominative Case

The Nominative Case

Nouns and adjectives in Russian can be in one of six cases, depending on their grammatical function in a sentence.

The nominative case is used when a noun is the grammatical subject or predicate of a sentence - that is, the person or thing who/that is performing the action described by the verb.

Nouns in Russian dictionaries appear in the nominative case (the 'dictionary form').

The nominative case answers the questions кто? (who?) or что? (what?).

In Russian in a sentence of the form 'A is B' the B (as well as A) should be in the nominative - that is to say the verb быть (to be) takes the nominative.

Examples:
	Это кресло уютное. This armchair is cosy. кресло (neu.) is the subject of the verb so is in the nominative
	Главный вокзал очень большой. The main station is very big. вокзал (masc.) is the subject of the verb so is in the nominative
	Мария там. Maria is there. Мария (fem.) is the subject of the sentence so is in the nominative
	Эта улица чистая. This street is clean. улица (fem.) is the subject of the sentence so is in the nominative.
	Тот дом новый. That house is new. дом (masc.) is the subject of the sentence so is in the nominative тот here is also in its nominative form
	Это стихотворение короткое. This poem is short. стихотворение (neu.) is the subject of the sentence so is in the nominative
	Эта площадь красивая. This square is beautiful. площадь (fem.) is the subject of the sentence so is in the nominative
	Чай свежий, а хлеб чёрствый. The tea is fresh, but the bread is stale. чай (masc.) and хлеб (masc.) are both subjects so are both in the nominative
	Такси уже здесь. The taxi is already here. такси (neu.) is the subject of the verb so is in the nominative
	Кто это? Это новый сосед. Who is that? That is the new neighbour. сосед follows the verb 'to be' so is in the nominative кто is also in its nominative form
	Что это? Это школа. What is that? That is a school. школа follows the verb 'to be' so is in the nominative. что is also in its nominative form
	Кто он? Он старый друг. Who is he? He is an old friend. друг follows the verb 'to be' so is in the nominative кто and он are also in their nominative forms
	Что это за далекий звук? What is that distant sound? звук follows the verb 'to be' so is in the nominative что этот за is the standard way to ask 'what is' something.