Because it is more dense as it moves toward its center, there is actually less movement of the head.

因为越靠近中央，密度越大，实际上磁头只需移动更短的距离。

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Resembling a bondage accessory and wrapped around her head, the mask’s spike-like pencils are drawn back and forth over a vertical sheet of paper, producing a dense scribble.

片中她戴上一个特殊的面罩，在上面她像安装附件一样固定了一圈一圈削尖了的铅笔。 然后她开始移动，这些铅笔在一张竖直放置的纸上前后运动，描绘出潦草密集的线条图案。

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A well-crafted beer produces a tightly knit, dense, uneven head comprised of small, uniform bubbles.

一杯优质的啤酒可以产生紧密浓稠的的泡沫，泡沫由很多细小一致的气泡组成。

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