It must have cost a tidy sum.

这准花了相当大的一笔钱。

《牛津词典》

He's put aside a tidy sum for his retirement.

他存了一笔相当可观的钱以备退休之用。

youdao

And heirs might end up with mixed feelings after learning they went for years without knowing they someday would inherit a tidy sum.

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For a tidy sum and some untidiness, Kinect enables the kind of motion-sensing gameplay that has become the Wii's hallmark without having to strap the controller to various limbs (as with EA Active for Wii).

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Many of the original holders of the bonds, weary of waiting for a deal, have sold them to others for as little as 12 cents on the dollar, so the purchasers of these bonds stand to make a tidy sum.

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