But which phase of this process is the most difficult to clear?

但是整个过程中的哪个阶段处理起来最难？

youdao

It is best not to do that, but when experimenting, these things can happen, and they can be difficult to clear up.

最好不要这样做，但在实验过程中，这些情况有可能发生，而且清除起来相当困难。

youdao

All of these actually difficult to clear the mathematical model and mathematical formulas are the only confirmed solvable.

所有这些实际上很难用明确的数学模型及数学公式给出唯一确定解的。

youdao

Needlessly the Egyptian striker struck a backpass from the halfway line that proved difficult to clear for Robinson.

BBC: SPORT | Football | FA Cup | Fulham 0-4 Tottenham

But it makes it very difficult to get a clear picture of how Zetia will perform for Schering-Plough, or of the company's future in general.

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It can be difficult to get a clear answer out of people who are uncomfortable with saying no in general, and of course attitudes may change.

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