private String[] get_category_words_of(String query)
{
String first = query.Split()[0]; // TODO: how about "For what reason does...?"?
String[] category_words = first=="when" ? time_words :
first=="where" ? place_words :
first=="whose" || first=="whom" || first=="who" ? person_words :
first=="what" ? identity_words :
first=="which" ? specifying_words :
first=="wherefore" || first=="why" ? explanation_words :
first=="how" ? mechanism_words :
/*auxilliary*/ truth_words; // e.g. "Is Santa Claus real?"
return category_words;
}