重新解释 223 -- 227 行

We draw a tangent at the peak, treating the area covered by the tangent and another inward intersection as the non-convex region. Its width should be as small as possible. One way is to depress the peak height, which is inevitable in inhomogeneous materials. The other way uses smaller rPMT to make the predicted PE decrease significantly.

这几句话十分难懂：

1. 横线是什么？
2. 阴影是什么？
3. 为什么阴影的宽度决定了 multimodality？
4. 最后两句 One way..., the other way ... 完全不理解。可以写中文吗？