Comparing and reasoning between these two types of estimates is very difficult to do—perhaps impossible.

比较解释这两种估算是非常困难的——也许是不可能的。

youdao

Simply put: it is difficult, if perhaps impossible, to deliver accurate real time results of the magnitude that Google would expect.

实际上Google很难，或者不可能，把即时、准确的搜索结果传达给用户。

youdao

A generation from now it may be too late to find an answer and perhaps impossible, in the stifling collective climate of that future time, even to ask the question.

或许一代人解决不了，或许在将来令人窒息的大众氛围下这种问题都不能提出来。

youdao

Yet separating policy impact from all of the other factors that affect market returns is exceedingly difficult (perhaps impossible).

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Perhaps impossible for some.

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The other is the very difficult, perhaps politically impossible, supply side reforms that would be needed in the southern economies to get them growing again.

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