正如在之前的图标中所示的，我们可以用实线来真实的描述那些在每层上出现的峰值。

As shown in earlier diagrams, we can visually illustrate those peaks on each tier with a solid line.

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如图10所示，一条带有闭合的单向箭头的点线意味着实现(或实施)；正如我们在图4中所见到的，一条带有闭合单向箭头的实线表示继承。

As shown in Figure 10, a dotted line with a closed, unfilled arrow means realization (or implementation); as we saw in Figure 4, a solid arrow line with a closed, unfilled arrow means inheritance.

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