The letter had come from an unknown mischief-maker.

这封信来自一个匿名的离间者。

《柯林斯英汉双解大词典》

Trenton was once the home of the world's largest maker of fortune cookies, very widely served in Chinese restaurants in America yet unknown in China, a fact which surprises most Americans.

特伦顿曾是全球最大的幸运饼产地，产品广泛供应美国的中餐厅，但在中国却一文不名，这让很多美国人都感到惊讶。

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The biggest winner in biotech last month was KV Pharmaceuticals, a heretofore unknown drug maker whose new drug to treat pre-term birth was approved but the Food and Drug Administration on Feb. 4.

FORBES: Biotech Busts And Breakthroughs For February

If any accessories-maker WAS going to get the new iPod early, we doubt it'd be some unknown company like Uniea.

ENGADGET: Uniea takes a gamble on iPod nano fatty, preemptively makes case for it