subcategories
Example:
In languages spoken by people for whom fishing is a major source of food, there may be many distinctions made in fishing-related activities, with a correspondingly complex lexicon. You can subdivide 226 Fishing into the following subcategories:
226.1 Fishing methods
226.11 Netting
226.11.1 Net casting
226.11.2 Net dragging
226.12 Spearing