And I add here that the construction lines don't appear in the final work.

我在这里添加了辅助线，但它们不会出现在最终成品中。

Many different designs are possible from the same construction lines just by picking different segments.

从相同的作图线中， 只要选择不同的部分就能得到许多不同的设计。

And now if we hide the tiles and just look at the construction lines, we see this.

如果我们隐去瓷砖，只看辅助线，就会看到这个。

And in order to draw these shapes, the medieval craftsmen who did this would have done them by using these construction lines.

要画出这些图形，中世纪的匠人会借助这些辅助线。

I've got several thousand hours of carrying sling loads, fire buckets, concrete buckets, doing power line construction, actual power poles.

我已经有数千小时的搬运吊索负载的经验了，消防桶、混凝土桶、电力线路施工、实际的电线杆。