In some industries, notably pharmaceuticals, it is doubtful that the huge investments needed to develop new products would be made without the prospect of patent protection.

在某些行业里，特别是医药行业，如果不能指望专利得到保护，是否真有人愿意投入研发所需的大笔资金是个让人质疑的问题。

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It was doubtful that the money would ever be found again.

钱是否能失而复得，实在令人怀疑。

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With just six weeks left before Chicago, it was very doubtful that he would be able to run a full marathon at a tempo one minute per mile faster than his best, current 5k!

我非常怀疑他能否在6周之后举行的Chicago马拉松上，以比他当时最好5 K每英里快1分钟的配速完成一个全程马拉松！

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An FTT on FX in the EU would be illegal and it is doubtful that anyone wants to go through the process of revising the basic treaty to change this.

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But other than that, the military, Dover Air Force Base, protecting it against any closing - although, that would be doubtful.

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It is doubtful, however, that Buffett would be interested in buying the whole enterprise.

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