Wrapping can be done in various ways. I’ll mention 2 of them:
1.) text wrapping – using white-space property http://www.w3schools.com/cssref/pr_text_white-space.asp
2.) word wrapping – using word-wrap property http://webdesignerwall.com/tutorials/word-wrap-force-text-to-wrap
By the way, in order to work using these 2 approaches, I believe you need to set the “display” property to block of the corresponding span element.
However, as Kirill already mentioned, it’s a good idea to think about it for a moment. You’re talking about forcing the text into a paragraph. PARAGRAPH. That should ring some bells in your head, shouldn’t it? 😉