For the purpose of this title certain terms are herewith defined. When not inconsistent with the content, words used in the present tense include the future, words in the singular number include the plural, words in the plural number include the singular; the word "persons" may be taken for persons, association, firm, copartnership or corporation; the word "structure" includes building; the word "used" includes designed or intended to be used; the word "shall" or "must" is always mandatory and not merely directive, the word "may" is permissive and the word "should" is a preferred requirement. (Ord. 518, 6-10-2008)