help with map making

[Dannyg333]

http://i1.tinypic.com/oj11z4.jpg go to this and read what my cprompt came up with when i tried to make my level i dont know why this happens could someone help me or tell me why this happens when i try to do this

[Soccerfreak]

You have a bad face, remake your BSP. or import the .wrl.

[Dannyg333]

what is a bsp and im not quite sure how to fix it could you write me a brief tutorial on how to fix it or remake it thanx alot because on my other previos maps the same error came up with all of them so i gta figure this out thanxx alot danyg333