君の誕生日

your birthday

→ 君
phrase Rare #23,894
your birthday 君の is a casual way to say “your,” typically used with someone familiar or of similar age. 誕生日 means “birthday.”
JA: 君の誕生日に何が欲しい?
EN: What do you want for your birthday?

私の誕生日君の誕生日日が近い

My birthday is around the same time as yours.

君の誕生日が近づいている

Your birthday is coming up.

明日は君の誕生日なのに行かなきゃ

Even though tomorrow is your birthday, I have to go.

— 鶴は翔んでゆく (1957)

君の誕生日来週

Is your birthday next week too?

— アバウト・タイム ~愛おしい時間について~ (2013)

今年の君の誕生日何曜日当たります

What day of the week does your birthday fall on this year?

君の誕生日には何を贈ろうかな

I wonder what I should get you for your birthday.