por su cumpleaños

for their birthday

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phrase Rare #28,459

for their birthday Used to say that something is given, sent, or done in celebration of someone’s birthday. The possessive su can mean his, her, your, or their depending on context.

SP: Le compré flores por su cumpleaños.

EN: I bought them flowers for their birthday.

Me gustaría regalarle algo por su cumpleaños.

I’d like to give them something for their birthday.

Siempre hacemos una fiesta por su cumpleaños.

We always have a party for his birthday.

Él escribió cartas con la pluma que le compré por su cumpleaños.

He wrote letters with the pen I bought him for his birthday.

Tom quería comprarle algo bonito a Mary por su cumpleaños.

Tom wanted to buy Mary something nice for her birthday.

Ella quiere algo muy especial por su cumpleaños.

She wants something very special for her birthday.

Ha venido a visitar a Tag por su cumpleaños.

He has come to visit Tag for his birthday.

— Hunting Season (2025)

No sé qué comprarle por su cumpleaños.

I don't know what to buy them for their birthday.