One reason this is hard is that radio telescopes must chop the spectrum into fine portions to study it, like tuning into a signal on a car radio.

研究工作进展困难的一个原因是，正如汽车收音机的调频一般，射电望远镜必须把光谱按照波段分成易于研究的片段。

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Often, when we are at one end of the spectrum, it's hard to remember the other end.

常常，当我们处在一个极端的时候，我们很难回忆起另一个极端。

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This variability has led many people to think of it as a spectrum of symptoms rather than a single, clear-cut syndrome. And that variability makes it hard to work out what causes it.

这种多变性令很多人认为它的症状多样而不是单一明确的，这种多样化加大了对其病因的研究难度。

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The other end of the spectrum is a market that is very hard to define.

这里的其他市场,是指很难有效定价的那些市场

耶鲁公开课 - 金融市场课程节选

And I also want to point out, it's guaranteed pretty much you may or may not be able to see, sometimes it's hard to see that one that's getting near the UV end of our visible spectrum. So we won't worry if we can't see that.

我要指出的是，我可以保证你们,但你们可能会看不到，有时候很难看到,这个可见光谱边缘接近紫外光地方的这根谱线,所以看不到也不用担心。

麻省理工公开课 - 化学原理课程节选

This week, the FCC issued a proposed ruling to commissioners, which according to insiders, is likely to end up being in Continental's favor, given that the Feds are the only ones who can tell you how to use your hard-earned unlicensed spectrum.

ENGADGET: FCC likely directing Logan to lay off Continental's WiFi

But even he will find it hard to straddle the entire political spectrum.

ECONOMIST: A question that worries a few and excites others

But such misallocations remain hard to rectify because of rigid spectrum zoning policies and a lack of clearly defined and tradable property rights.

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