生日快樂的英文為：happy birthday
例句：
1.蛋糕上裱了“生日快樂”的字樣。
The cake had'Happy Birthday'piped on it.
2.我祝她生日快樂。
I wished her a happy birthday.
3.我們全都湧進她的辦公室，唱“祝你生日快樂”。
We all crowded into her office to sing'Happy Birthday'.
4.媽媽，生日快樂！
Happy Birthday,Mum.
5.生日快樂，親愛的。
Happy birthday,sweetheart.
6.生日快樂！
Happy Birthday!
7.祝您生日快樂！
Happy birthday to you!
8.他在蛋糕上鑲上了“生日快樂”的字樣。
He piped"happy birthday"on the cake.
9.全班學生一起對着老師唱起了《生日快樂》歌。
The whole class all joined together to sing happy birthday to the teacher.
10.全年生日快樂！
Happy Birthday All Year!
補充：
birthday party生日聚會
birthday cake生日蛋糕
birthday card生日賀卡
birthday
n.生日，誕辰；誕生的日子
happy
adj.幸福的；高興的；巧妙的
n.(Happy)人名
