    Sentence 1: The answer has nothing to do with their cause,  however, but with the simple fact that dictionaries are not  exercises in bi-unique substitutability; in other words, ifone of  the senses of run is ‘operate’ (as in She runs an engine factory  ), that does not make it valid to assume that one can substitute  operate for run in We run in the marathon every year .  Although recognizing this as a shortcoming of dictionaries and  assigning it arbitrarily to what, for lack of a better term, we  ‘might call the genius of the language, might seem trivial to the  ‘casual observer, it is a valid matter for concern in the realm of  exicology.    Sentence 2: The answer given is irrelevant to their cause.    