He piped "happy birthday" on the cake.
他在蛋糕上镶上了“生日快乐”的字样。
Happy Birthday All Year!
全年生日快乐！
Last Friday, after he arrived at the school, instead of finding garbage to clean up, he found almost 800 students lining the hallways with handmade cards, blowing noisemakers and singing a full-throated happy birthday to him ．
上周五,他来到学校后,发现没有垃圾需要清理。他看到近800名学生在走廊里成队列站着，他们拿着手工卡片,吹着扩音器,为他大声唱着生日快乐歌。
In those days people sent birthday cards when they couldn't wish somebody a happy birthday in person ．
那时候，当人们不能亲自祝某人生日快乐时，他们就会寄生日贺卡。
Do you know that the "Happy Birthday to You" song is the first song sung in outer space?
你知道"祝你生日快乐"这首歌是第一首在外太空被唱响的歌吗？