MyBB Community Forums

I just created a forum and several other forums under that....How can I change the URL of my forum?
For example here is my Forum URL
www.onelifeoneking.com/forum
then I have several other forums once you click on the above link such as:
Bodybuilding
www.onlifeoneking.com/forum/forum-3.html

My question is....How can I change the URL for my bodybuilding section to read as
Bodybuilding
www.onelifeoneking.com/forum/bodybuilding.html


Pleas Help Ive search for the answer but have come up with nothing.
Thank you

you can use Google SEO plugin - http://mods.mybb.com/view/google-seo