你知道在美国有百分之二十到三十的青少年在这个时期都过得很艰难吗？

Do you know twenty to thirty percent of teenagers in the US have a hard time going through the period?

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你知道我们什么时候到的吗？

Do you know what time we got there?

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你知道吗？观察到宽吻海豚可以跃出水面高达16英尺(4.9米)，用它们的后背部或侧面飞溅着陆。

Did you know? Bottlenose dolphins have been observed to breach up to 16 feet (4.9 meters) out of the water, landing with a splash on their back or side.

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But finally, Reiner says, well, thank you for visiting us, it's all very wonderful, but you know our audience would really like to know; it seems like a simple question but it's awfully hard to understand, but how can a great, big, enormous, heavy thing like this airplane get off the ground?

但最后 雷纳说到,谢谢你的来访,太棒了,但你知道吗,我们的观众非常想知道,这问题貌似简单,但却很难让人明白,问题是,像这么一个巨大且沉重的飞机,是如何飞起来的呢

耶鲁公开课 - 古希腊历史简介课程节选