birthday是可數(shù)名詞嗎

　　It's my birthday a week on Tuesday.

　　一周后的星期二是我的生日。

　　I'm getting a bike for my birthday.

　　我過生日時(shí)會(huì)得到一輛自行車。

　　She sends me a card on my birthday.

　　她在我生日那天送了一張賀卡。