YOU SAID:
hey, what's your birthday
INTO JAPANESE
ねえ、あなたの誕生日は何ですか
BACK INTO ENGLISH
Hey, what is your birthday
INTO JAPANESE
誕生日はいつ?
BACK INTO ENGLISH
What is your birthday?
INTO JAPANESE
誕生日はいつ?
BACK INTO ENGLISH
What is your birthday?
That didn't even make that much sense in English.