1, in the center of the canvas, write down the theme of this unit "Understanding and Application of Numbers".

2. Draw subtopics such as "number reading", "number ratio", "number addition" and "number subtraction" under the theme, and connect them with the theme with lines.

3. Draw sub-themes such as "number sequence" and "number size comparison" under "number reading" and connect them with lines.

4. Draw sub-themes such as "the relationship between numbers" and "the comparison between numbers" under "the comparison of numbers" and connect them with lines.

5. Draw sub-themes such as "combination of numbers" and "addition of numbers" under "addition of numbers" and connect them with lines.

6. Draw sub-themes such as "cognition of graphics", "classification of graphics" and "application of graphics" under "cognition and application of space" and connect them with lines.