It's not firsthand information.

那不是第一手资料。

youdao

It's not firsthand information, so I don't believe it.

这不是第一手资料，所以我不会相信。

youdao

Thankfully, most Americans do not know, at least not firsthand.

谢天谢地，大多数美国人并不知道答案，至少他们并没有亲身体验过。

youdao

Allegations of voting irregularities are widespread and international monitors acknowledge they were not able to observe firsthand what took place in many provinces because of poor security.

VOA: standard.2009.08.22

To be sure, the Daily News story reports that Kathy LeMond was not a firsthand witness to this alleged payment.

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The ARRT said this week that they did not punish Kwiatkowski because they did not have firsthand evidence of the 2010 incident.

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She ought to have remembered that real news, even real gossip, begins in what is observed firsthand, not secondhand.

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