Parts of a chapter in a book or a law.
Subchapters help organize information into smaller sections.
Examples:
The book has many subchapters about animals.
Each subchapter talks about a different kind of food.
In the subchapter about birds, it says they can fly.
The subchapters in this book are like little stories.
The subchapters in this book are so many, it's like a library!
I like the subchapters about space the best.