To say=decir. To speak=hablar.
español / española / españoles / españolas (nationality)español / castellano (language)
This is actually a bit more complicated than it sounds! The easy answer is: "to do" = "hacer" which is the infinitive form (not conjugated, that is does not indicate a person or time) When you...
bee = abeja. queen bee = abejon
I am = Soy Am = Oy