три письма

three letters

→ три
phrase Rare #37,750
three letters Письма can mean written letters or emails/messages, depending on context. After три, the noun is in the genitive singular: письма.
RU: Я получил три письма от своей сестры.
EN: I received three letters from my sister.

Том написал три письма.

Tom wrote three letters.

Было три письма.

There were three letters.

Я написал вам три письма.

I wrote you three letters.

На прошлой неделе я получил от Тома три письма.

Last week I received three letters from Tom.