She's a bit of a mystery!

她这人有点来历不明!

《简明英汉词典》

This truck is of unknown origin.

这辆卡车来历不明.

《现代汉英综合大词典》

His inexplicable debts were a byword in his circle.

他那些来历不明的借款成为那圈子里人议论的话题.

辞典例句

The physicians at first laughed at the unknown wayfarer.

医生们起先嘲笑这个来历不明的旅行者.

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Do not read mails and attachment.

不要阅读来历不明的电子邮件及其附件.

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Dont use the unknown floopy disks.

不要使用来历不明的软盘.

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He's a bit of a mystery!

他这人有点来历不明!

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