The reciprocal pronoun (друг друга)

Saying "Each Other": друг друга

To express mutual actions or relationships—meaning "each other"—Russian uses the phrase друг друга.

In this phrase, the first word (друг) is locked; it never changes. The second word (друга) declines, changing its ending to match the grammatical case required by the verb or preposition in the sentence.

Prepositions Go in the Middle

The most important rule for друг друга is how it interacts with prepositions. Whenever a preposition is required, it splits the phrase and sits directly between the two words.

For example, the preposition от (from) requires the genitive case. To say "from each other", the preposition goes in the middle: друг от друга.

The exact same splitting rule applies to the preposition в (into), which takes the accusative case here (друг в друга).

Working with Other Cases

When you use a preposition that triggers the dative case, like к (to/toward), the second word changes its ending to match: друг к другу.

Direct Objects

When "each other" is the direct object of a verb, you do not need a preposition. The phrase remains друг друга, serving as the standard accusative direct object.

The Instrumental Case

Finally, when a verb requires the preposition с (with), the second word takes the instrumental case. The resulting phrase is друг с другом (with each other).