The whole argument rests on a false assumption.

整个论证都是基于一个错误的假设。

《牛津词典》

His actions were based on a false assumption.

他的行为基于错误的设想。

《牛津词典》

This is a false assumption.

这是一个错误的假设。

youdao

Now,it turns out that that assumption, standardly built into the usual label,may be false.

现在似乎在通常标签下建立的，这个假设本身就是错误的。

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This argument rests on a false assumption, that the Middle East was stable to begin with.

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The game itself turned on a false assumption, suggesting a deeper fault in the system.

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Which leads to the next false assumption in the sentence in question.

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