大量的在线讨论区涌现，人们在这里讨论与上网时间过长有关的负面经历。

Scores of online discussion boards have popped up on which people discuss negative experiences tied to too much time on the Web.

youdao

此外，还涌现了大量的在线讨论区，人们在这里讨论与上网时间过长有关的负面经历。

And scores of online discussion boards have popped up on which people discuss negative experiences tied to too much time on the Web.

youdao

加入Rational开发工具讨论区。

Join the discussion in the Rational Development Tools forum.

youdao

So, for example, we have this average level, and then it can go high where we have the peak, or it can go very low. We can also discuss sound waves, so again it's just the periodic variation of some property -- in this case we're talking about density, so we have high density areas and low density areas.

例如这是平均位置，在峰的位置水位高，在谷水位低，我们也可以,讨论声波它也是某种,量的周期变化，在这里我们,讨论的是密度,我们有高密度区和低密度区。

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