The construction mode of mathematical mind map is to determine a central theme, lead out sub-themes, and then divide the sub-themes into levels. The specific operation steps are as follows.

1, use the most concise language to determine the mathematical theme to be drawn. Take "angle measurement" as an example. As shown in the figure below.

2. An angle is a figure composed of two rays drawn from a point. So get to know the rays first. As shown in the figure below.

3. Draw line segments and straight lines with rays and compare their similarities and differences. As shown in the figure below.

4. For important knowledge points about angles, you can mark keywords on the mind map. As shown in the figure below.

Precautions:

In the mind map above, the definition of light is derived from angle, and a relationship line is drawn between angle and light, which is convenient for us to connect knowledge points in series.