The seventh day is commonly referred as the "day of man", and in most parts of China people will eat noodles as they symbolize longevity in Chinese culture.

初七是“人日”，中国各地人民都会吃面条，因为面条在中国文化里寓意长寿。

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Knowing we were celebrating the birthday, the waiter sent me a bowl of longevity noodles.

知道我们在庆祝生日，服务业还送了我一晚长寿面。

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In Putonghua, long (chang) and slim (shou) is similar to the pronunciation of longevity (changshou). Noodles are the most popular staple food on birthdays for the Chinese.

有一个说法是，面的形状长而瘦，谐音长寿，面条于是当仁不让地成为讲究讨口彩的中国人最受欢迎的生日主食。

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