blue ink

基本解释

If the charge moves to the bottom, the dark particles will show, giving the appearance of blue ink.
如果正电荷加到下方，黑粒子将显现出来，给出蓝墨水的痕迹。
Sign the contract in blue ink, not black ink. This, too, will make it easier to differentiate the signed original contract from photocopies.
最好用蓝墨水而不是用黑墨水来签署合同，因为蓝墨水可以很容易地让人区别出哪个是合同正本，哪个是影印副本。
www.chinadaily.com.cn
Her gaze dropped to the files stacked so neatly in front of her. She spotted a streak of blue ink staining the sleeve of her lab coat.
她盯着桌上堆放整齐的两叠文件，却一不小心余光扫到白大褂袖子上的一道蓝墨水。

First, though, the blocks are tested with red and then blue ink and corrections are made to the carving.
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Outside a polling station in the wealthy suburb of Petionville, Zephyr Watson(ph) shows his thumb which was dipped in blue ink when he voted half an hour before.
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