В соседнем доме живёт мой друг.

the friend

Breakdown of В соседнем доме живёт мой друг.

• дом: the house
• мой: my
• в: in

Questions & Answers about В соседнем доме живёт мой друг.

What does «в соседнем доме» literally mean, and what case is доме in?

Literally, «в соседнем доме» means “in the neighboring house” or “in the house next door.”

• в = in
• соседнем = neighboring / next‑door (adjective, masculine/neuter, prepositional case, singular)
• доме = house (noun дом, masculine, prepositional case, singular)

So доме is in the prepositional case, because it follows в and answers the question “где?” (where?).

Why is it соседнем and not соседний?

Соседний is the dictionary form (masculine nominative singular). In the sentence, the adjective has to match доме (prepositional masculine singular), so it changes:

• Nominative: соседний дом – “a neighboring house”
• Prepositional: в соседнем доме – “in the neighboring house”

The endings change like this:

• Masculine adjective -ий → -ем in the prepositional case:
  • соседний → соседнем
• Masculine noun дом → доме in the prepositional case

Adjectives in Russian agree in gender, number, and case with the noun they describe, so соседнем must match доме in the prepositional case.