It's a white marker.

这是一只白色的马克笔。

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All scaffold should be marked by white marker before block final inspection, the marker should be rotundity and easily was found;

分段完工前，外壳上脚手架接触处用白色记号笔标出，圆形且易于发现；

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The Japanese commander buried brigadier Lawson the next day and erected a white marker on the grave with the brigadier's name and rank written on it in Japanese, a rare honor.

第二天，日本指挥官下令埋葬了劳森准将，并在墓前竖起了一块白色的碑，上边以日文写着准将的名字和军衔，这算是一种罕见的荣誉。

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