"The cat eats bread."
Translation:El gato come pan.
Because they are not referring to any particular bread, just bread in general. But if you mean a particular bread you have to use "El" in front of it, because "Pan" (Bread) is a masculine word in spanish, which should always have "El" in front. The main rule is: "La" in front of feminine words and "a-ending" if you are refering to a feminine word or a female and "El" in front of a masculine word that also should have an O-ending, and also if you are fering to a boy/male. Pan is a special word because it does not have the main "masculine O-ending", but it´s still a masculine word and should therefore have "El" in front of it.