First of all use a black marker or a felt-tipped pen to draw your characters.

首先使用一个黑色标志或觉得核弹头笔提请你字符。

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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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