Russian Pronouns: Relative Pronoun [который]

Не руби сук, на котором сидишь.
Don’t bite the hand that feeds you.
[saying]
Introduction

Time to learn some relative pronouns. Well, a relative pronoun.

Today’s lesson will be focused completely on который, which is a key relative pronoun in Russian.

Purpose

The word который has more than one meaning, but when used as a relative pronoun, it carries the meaning of, depending on context, that, who[m], which, whose, etc.

A relative pronoun is used to connect a relative clause to the main clause of a sentence. A clause is a sentence with a subject and predicate [the man is rich].

Maybe this will be clearer for you:
The man is rich. [main clause]
The man buys expensive items. [additional information]
The man who is rich buys expensive items.
Of course, in everyday speech this sentence could be simplified to the rich man buys expensive items. Relative pronouns are more common in writing but have their place in everyday speech.
Relative clauses help clarify or provide additional information to the subject or object in a sentence.
Some prime examples for better understanding:
The woman who is wearing a yellow dress is sitting beside me.
The computer that is in the corner of the room is mine.
The matter about which you speak doesn’t concern me.
The children whose clothes are red are on the opposite team.
The man whom I know best is my father.

Formation

Although который is a relative pronoun, it declines just like an adjective.

Below, you’ll find the full declension of this pronoun.

m.f.n.pl.
nom.которыйкотораякотороекоторые
gen.которогокоторойкоторогокоторых
dat.которомукоторойкоторомукоторым
acc.который
которого
которую
которое
которого
которые
которых
instr.которымкоторойкоторымкоторыми
prep.которомкоторойкоторомкоторых

This pronoun must agree in gender, number and case with the noun is modifies.

Some examples for better understanding:

Two ClausesOne Relative Clause
Это мужчина.
Он работает в магазине.
This is a man.
He works in a shop.
Это мужчина, который работает в магазине.
This is the man who works in the shop.
Это девушка.
Она работает в магазине.

This is a girl.
She works in a shop.
Это девушка, которая работает в магазине.
This is the girl who works in the shop.
Это пальто.
Оно стоит в продаже.
This is a coat.
It’s for sale.
Это пальто, которое стоит в продаже.
This is the coat that’s for sale.
Это люди.
Они работают в магазине.

These are people.
They work in a shop.
Это люди, которые работают в магазине.
These are the people who work in the shop.

More challenging examples:

Это девушка.
Я влюбился в неё с первого взгляда.

This is a girl.
I fell in love with her at first sight.
Это девушка, в которую я влюбился с первого взгляда.
This is the girl with whom I fell in love at first sight.
Это мужчина.
Я знаю его с детства.

This is a man.
I’ve known him since childhood.
Это мужчина, которого я знаю с детства.
This is the man I’ve known since childhood.
Это пальто.
Я купил его для тебя.

This is a coat.
I bought it for you.
Это пальто, которое я купил для тебя.
This is the coat that I bought for you.
Это люди.
Я видел их там.

These are people.
I saw them there.
Это люди, которых я видел там.
These are the people whom I saw there.

Even more examples:

Павель, дети которого учатся в этой школе, станет новым директором.
Pavel, whose children attend this school, will become the new director.
Женщина, у которой я купил цветы, работает на утреннем рынке.
The woman, from whom I bought the flowers, works at the morning market.
Город, в котором я живу, находится в Калифорнии.
The city in which I live is located in California.
Дом, у которого стены зелёные, недадно был продан.
The house whose walls are green was sold recently.
Язык – это мост, который соединяет разные культуры.
Language is a bridge that connects different cultures.

Well, that concludes today’s lesson.