Authors use graphic aids to illustrate and expand on concepts taken up in the text because graphics are yet another way of portraying relationships and clarifying connections.
作者使用图形辅助来说明和扩展文本中的概念，因为图形是描述关系和阐明联系的另一种方式。
2
Let's close by clarifying a couple of key issues.
让我们通过澄清两个关键问题来结束本文。
3
The most important use is in clarifying my own thinking.