Breakdown of Ты единственный друг, который всегда остаётся со мной.
я
I
ты
you (singular)
друг
friend
всегда
always
Questions & Answers about Ты единственный друг, который всегда остаётся со мной.
Why do we use единственный here instead of один for "only"?
While this lesson covers один meaning "alone" or "only" (as in "only one"), when you want to describe someone as "the only [noun]," you must use the adjective единственный. Saying ты один друг would sound strange, more like "you are one friend" rather than "the only friend."
If I am talking to a female friend, would I change который to the feminine form которая?
No, because который must match the grammatical gender of the noun it directly refers back to. Here, it refers to друг (friend), which is a masculine noun. Even if the person is female, the grammatical word друг dictates that который must be masculine singular.
Why is the verb остаётся in the "he/she/it" form when the sentence is about ты (you)?
The sentence is split into two clauses. In the second half, the grammatical subject is который (who), which stands in for друг (friend). Just like in English where we say "the friend who stays" rather than "who stay," Russian uses the third-person singular form остаётся to match it.
Why does the preposition с (with) become со in the phrase со мной?