On someone's birthday.
Everyone shares their birthday with someone or another.
No, everyday is someone's birthday
Thank you very much! (if it's your birthday) I think you have me confused with someone else, it's NOT my birthday. (if it's NOT your birthday)
Hello, and Happy birthday.
A birthday card is a greeting card given to someone to celebrate his or her birthday.
When someone wishes you Happy Birthday, it is usually because it is on or near your birthday, unless, for some reason, they are being sarcastic.
Of course it's right on the day of your birthday!
if its close to your birthday than ask them for it on your birthday.
Yes
No, you say Happy Birthday to someone to congratulate them on their birthday. You say Happy Anniversary to a couple who are celebrating their anniversary together.
If someone was born in 2044, they will celebrate their 100th birthday in 2144.