Two Strings Combined?

I'm using build 241 for MMF2, and I was wondering if it's possible to do something like Global String A and Global String B in an expression? For example, I have the user set the directory path to Program Files\Cool People\ and then I want to tack on the next folder down, like Program Files\Cool People\Movies, but not having the user enter that. Hence why I would like to know how I can have two strings in the same expression.

Example....

Global String A + Global String B + ".txt"

Nice speedy reply! Thanks, that makes it work, I'm just trying out my first app and learning how everything runs. :)