It is difficult to quantify an exact figure as firms are reluctant to declare their losses.

很难确定一个准确的数字，因为各家公司不愿公布它们的亏损情况。

《柯林斯英汉双解大词典》

Agriculture proves very difficult to quantify because of the constantly changing conditions involved.

因为所涉及的条件不断变化，所以农业很难量化。

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Qualitative probability (low, high) values can be difficult to quantify.

定性的可能性(低，高)值非常难以量化。

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In a field where outcomes are difficult to quantify, Morgan insists on showing results beyond spruced-up buildings.

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The main problem is that the complexity of computer networks makes it very difficult to quantify risk accurately.

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As a non-sales, non-marketing, non-manager, I find it difficult to quantify my achievements.

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