It's all about making the traveling experience less stressful and blue is said to induce a feeling of calm.

这一切都是为了让飞行体验不那么紧张，据说蓝色可以让人产生一种平静的感觉。

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To describe a depressed person, you say that the person is "feeling blue".

你会说某人“feeling blue”来形容这个人很沮丧。

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Yes, it can be costly, but so too is making decisions about closing a business when you are feeling blue.

的确，这耗费巨资，但总比在你感到忧郁的时候做出关闭企业的决定要好得多。

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You know that feeling on a clear blue sky day.

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"It's a very reassuring feeling to turn on the stove, see that blue flame and know you had a part in bringing a stable energy source to your community, " Glenn says.

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And they will not be able to receive surprise presents, like special cookies or favorite movies, which are often brought to the space station on supply shuttles when someone starts feeling homesick or maybe a little blue.

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