绿色螺旋线由内部每一个正方形和四分之一圆相切线构成，而红色的螺旋线是黄金螺旋线，它是对数螺旋线的一种特殊类型。

The green spiral is made from quarter-circles tangent to the interior of each square, while the red spiral is a Golden spiral, a special type of logarithmic spiral.

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用最明显的图形来描述这个过渡的特性就是：当在两个圆之间绘制一条直线，直线与每个圆只有一个交点时，那么这条线就是两个圆的切线。

The quality of this transition is best visualized by a straight line drawn between two circles: the line's only point of contact with each circle is tangential.

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我需要画出这个圆的一条切线吗？

Do I need to draw a tangent line of this circle?

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