But it is always hard to pin down.

但这始终是难以确切说明。

youdao

Mr Obama's views are hard to pin down.

奥巴马先生的观点则很难确定。

youdao

A trader's intent is hard to pin down, however.

然而，交易商的意向是很难被抑制的。

youdao

One of the reasons for thinking it's not clear whether the argument fails or not is because it's hard to pin down, where exactly did it go wrong?

并不能确定这个论证是否成立,的其中一个原因就是,我们很难确定,到底是哪里出了问题

耶鲁公开课 - 死亡课程节选

Trading in private shares is growing rapidly, though it's hard to pin down exact numbers.

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The stylized action game is actually hard to pin down to a single genre.

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Torrents are scattered, diverse and hard to pin down, and that makes them incredibly hard to stop.

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