But it's crucial to use the sharpest knife possible in trimming the essential from the secondary.

但是关键是把最锋利的刀刃用在发现事物的本质上。

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A device for trimming paper to desired dimensions, typically a ruled board with a long pivoted cutting knife attached to one side.

裁纸刀，切纸机：一种把纸张裁剪到所需尺寸的器具，通常有一个一旁装有一把有转轴的长裁剪刀的直边。

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At the time of folding, the knife will push the thread into the fold. After gathering, heat is applied to melt the trimming and forwarding.

折页时，折刀把线推入折口。集帖后，加热把线融化，粘牢各书帖，然后裁边及作进一步加工。

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