I just asked a [related question][1], and in German, it is not entirely clear what two consecutive relative pronouns "was" each qualify.

>{German}: Es gibt ***nichts***, ***was*** er sagen könnte, ***was*** die Tatsache ändern oder auch nur rechtfertigen würde.

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In English, on the other hand, two relative pronouns do not seem to give rise to ambiguity, especially since the first "that" can be omitted.

>{English}: There's ***nothing*** (***that***) he could say ***that*** would change or justify the fact.


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Then I wondered how I would express the same idea in French, and the following construction came to mind first. I notice I kind of *finessed* the issue of a relative pronoun pile-up by not using the second.

>{French}: ***Rien*** de ce ***qu***’il dirait ne pourrait changer ou justifier ce qui a été fait..

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But in spontaneous speech, you cannot always start a sentence *ideally* and yet might try to construct the rest of the sentence somehow with what you have started.

So what if you start off with "Il n'y a rien ..." instead and need to incorporate two relative pronouns somehow, just as is the case with the German and English sentences?

This might prove to be a more complex structure than the one I suggested above, but how would you go about it without causing ambiguity?

>Il n'y a ***rien*** ... {with two relative pronouns}


  [1]: https://german.stackexchange.com/questions/36091/how-to-interpret-two-consecutive-wass