Some flu experts say you should keep going for the time it takes to sing Happy Birthday twice.

有些流感专家说你应该持续洗唱两次“生日快乐”的时间。

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One year later, they began to sing happy songs in the cage. It seemed that they'd grown used to this artificial surrounding.

一年以后，它们对这个人工环境已经习惯，它们在笼子里歌唱着，显得很高兴。

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Mama is making a cake for me for tonight, and when Papa comes home everybody will sing happy birthday, happy birthday to you.

妈妈正在为我做晚餐蛋糕。等爸爸回来，所有人都会给我唱生日快乐歌。

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Free conference call services mean your entire clan can sing happy birthday to you at the same time.

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When we're done, before I leave, we're going to sing happy birthday, okay?

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That means you should stand there at the sink for as long as it takes to sing happy birthday twice.

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