没有确凿证据表明摄入维生素A会导致先天缺陷。

There was no positive evidence that any birth defects had arisen as a result of Vitamin A intake.

《柯林斯英汉双解大词典》

芭芭拉·哈格蒂在她的新书《重新设想生活》中写道：“事实上，除了几十年前进行的一些小规模试点研究外，几乎没有确凿证据证明中年危机的存在。”

"In fact, there is almost no hard evidence for midlife crisis other than a few small pilot studies conducted decades ago," Barbara Hagerty writes in her new book, Life Reimagined.

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没有确凿证据可以证实这些指控。

No independent evidence has emerged to corroborate these accusations.

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And it became common to reject any ancient story that wasn't really nailed down very, very firmly by some device.

越来越多的人开始不相信那些远古的故事,因为它们没有确凿的证据和可靠的说法

耶鲁公开课 - 古希腊历史简介课程节选