spoken是动词speak的过去分词形式，在句中作定语，修饰主语language, spoken 与 language有被动关系。该句可以理解为

What’s the language (which is) spoken in German?

youdao

最后我想对大家所熟知的一句表达作以修改，一句表达作以修改，我想简单地总结说，通向现实的路是用你的意图铺成的，不管是好是坏。

Finally to adapt an expression with which you're probably familiar I'll conclude simply by saying that the road to reality is paved with your intentions be they good or bad.

youdao

So Saint Peter concludes with -- it goes on, and he concludes with a couplet that is as terrifying in its threat of finality as it is for me utterly baffling in its significance.

因此圣彼得以一句如同这首诗结尾的威胁般,可怕的对句作了总结,我很难读出这句话的重要性。

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And they end this paper with the following quote: "It may be that trying to be happier is as futile as trying to be taller " and is therefore counterproductive."

论文用以下这句话作结尾：,“想变得更快乐,和想变高一样徒劳,只会适得其反“

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