The black-light pen or watermark stylus was a specialized felt-tipped marker originally designed by museums, restores, and forgery police to place invisible marks on items.

黑光笔或曰水印笔是一种特殊毡头标记笔，原由博物馆、修复专家或反赝品警察设计用来在物品上作隐形标记用的。

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The first group had their plumage colour enhanced with a marker pen.

第一组鸟的羽毛被用彩笔加强了色彩。

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The company mainly produces roller-tip pens, ball point pens, Gel ink pen white board marker permanent marker, mechanical pencil and other stationeries.

公司主要生产水性笔、中性笔、圆珠笔、白板笔、记号笔、活动铅笔等文化用品。

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Unfortunately for Tom Johnson, after three years of trying to grow any form of facial hair, he has been resigned to use the dreaded marker pen as a substitute.

BBC: Clive Stuart-Smith column

Different materials were handled roughly, placed in water, burnt, scoured with an abrasive cleaning pad and covered in black marker pen, but the laser was still able to read the surface fingerprint.

BBC: NEWS | Technology | Laser spots paper 'fingerprints'

Their black marker pen censored three per cent of the report for "legal reasons".

BBC: Savile inquiry: Media reaction to BBC transcripts