Mamá (Mom) & Agua (water)
-A proud Mommy
He only uses them when they're directed at the correct object (ie. Mom, or some form of water, be it on a glass, bathtub, etc.). He also says "aba" but we haven't figured out what that means yet.
Of course, Ben recognizes many other words that he doesn't speak yet. But he will turn in (or grab or go to) the right direction/thing when he hears them.
And to continue our bragging, he also plays soccer (dribbles while walking holding to our hands). He cruises all over the place now, holding on to furniture or his "walking car". He reads several books lifting the flaps to discover whatever is hiding underneath, and now crawls the right way (no more GI Joe). He even brushes his teeth.