Could you give some specific examples?
To understand this, follow these steps:
1) Install a fresh WordPress
2) Install bbPress
3) Create Forum + subforum + Categories + subcategories
Now, have fun with new games: “find out how to display a forum”, “read all warnings”, “discover the secret to download an additional language” and so on…
About additional languages, what is the mysterious secret that helps to understand where they are hidden?
Start your treasure hunt:
bbpress.org
Where are hidden additional languages? In the download section? Too easy.
My opinion, bbPress is designed for you to spend time.