This nebula is a bubble, and it's a bubble because intense blasts of stellar wind and radiation for a nearby star have cut through the dust and hollowed out the middle.

此星云呈泡沫状，之所以如此，是因为附近一颗恒星发生剧烈爆炸，产生的辐射和恒星风从尘埃云中间穿过，掏空了中间部位。

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First came the dotcom bubble, then the housing bubble.

首先是互联网泡沫，然后是房地产泡沫。

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There is no tech bubble, just a micro bubble here or there.

并没有所谓的高科技泡沫，只是一些小型的泡沫而已。

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He or she then blows through the pipe so that the glass expands into a rounded bubble form.

VOA: special.2009.09.16

And it's the windows in the firmament that are opened--those waters are allowed to rush in and dissolve that air bubble.

而在天空上有个口,水可以从中涌入，溶解这些气泡。

耶鲁公开课 - 旧约导论课程节选

Then lastly, there are things like the Internet bubble, they're not usually called this, but--the lending bubble where--or the subprime mess.

其次，市场上还存在像互联网泡沫，不经常被提及的贷款泡沫,此外还有次贷危机。

耶鲁公开课 - 金融市场课程节选

Oil was in a bubble of its own, well beyond the general commodity bubble.

FORBES: What Is Gold Telling Us?

Bubble or no bubble, market participants are expecting more record breaking highs for gold next year.

FORBES: Gold Bulls Dominate Montreal Precious Metals Conf; Forecast 2012 Prices

Another big difference between this bubble and the dot-com bubble is supply and demand.

FORBES: Here Comes Bubble 2.0, Which Is Just What The Economy Needs