This is the 7th most frequent Russian word.
за
The Russian word "за" can mean "behind," "beyond," "for," or "in favor of," depending on context.
The preposition 'за' indicates following or going after someone.
Я пойду за тобой.
I will follow you.
The preposition 'за' expresses the reason or cause of gratitude (for).
Она благодарна за помощь.
She is grateful for the help.
The preposition 'за' is used to indicate a location behind or beyond something.