The contract was awarded to a previously unknown company.

该合同给了一家先前不知名的公司。

《柯林斯英汉双解大词典》

The scientist confirmed the snake was a previously unknown species after conducting a genetic analysis of tissue samples.

在对组织样本进行基因分析后，科学家确认这条蛇是一个此前不为人知的物种。

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The team was led by Dr. Graham Reynolds, from Harvard University, the scientist confirmed the snake was a previously unknown species after conducting a genetic analysis of tissue samples.

该研究小组由哈佛大学的格雷厄姆·雷诺兹博士带队，这位科学家在对组织样本进行基因分析后，确认这条蛇是一个此前不为人知的种类。

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The plan follows months of deadlock over Iran's nuclear program and the recent discovery of a previously unknown nuclear-enrichment plant near the Iranian city of Qom.

VOA: standard.2009.10.19

Researchers have determined that dolphins found in southeastern Australia represent a previously unknown species.

BBC: New species of dolphin discovered

By doing so, they can identify previously unknown viruses and perhaps stop them before they spread.

CNN: Tracking deadly viruses' spread from animals to humans

Researchers believe there may be dozens of other species, previously unknown to science, hidden in the area.

CNN: ASIANOW - TIME Asia | 'There Was Method to My Madness'