Skin color, where you live and how much skin you have exposed all affect how much vitamin D you can produce.

皮肤颜色、生活地点和暴露在外的皮肤面积大小，都会影响你的身体所能产生的维他命D的量。

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Although we talked about Vitamin D and sunlight, it can make a huge difference in how you feel if you go to a tanning salon to get some light on your skin.

尽管我们已谈到维生素D和阳光，但是如果你刻意去参加日晒沙龙来摄取阳光到皮肤的话，它会让你感觉到巨大的差别。

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So how much is enough vitamin D?

这样人体要获得多少维他命d才算够了呢？

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Here is part of it. "I used to try on Mommy's jeans, just to see how they'd fit on me.

VOA: special.2009.04.27

Now the question you'd need to ask yourself is how do you know this didn't happen to you last night?

现在你要问自己的问题是,你怎么知道,昨晚你没发生这样的事？

耶鲁公开课 - 死亡课程节选

I'd be interested to know, gentleman down here, how do you do this?

我很好奇,我想知道,下面这位男士,你是怎么听的

耶鲁公开课 - 聆听音乐课程节选

Dr. Snyder may have found one in his serendipitous discovery of how D-serine functions.

FORBES: Repairing The Brain

Maybe the Internet industry is finally starting to get the hang of how D.

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Snyder may have found one in his serendipitous discovery of how D-serine functions.

FORBES: Repairing The Brain