He suffered from a certain difficulty in speaking.

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So there's risk involved and a certain degree of difficulty in actually making the contact and getting to the right people.

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One difficulty seems to be a certain disregard for statistical rigour.

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Gymnastics scrapped its perfect-10 high score in 2006, replacing it with one that was supposed to remove some human error by instituting one score for the difficulty achieving certain moves, alongside a second, more subjective score for execution.

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