Unless the context otherwise requires, the following
definitions shall be used in the interpretation and administration
of the chapter. Words used in the present tense include the future;
the singular number shall include the plural, and the plural the singular;
the word "structure" shall include the words "arranged," "designed,"
"constructed," "altered," "converted," "rented," "leased" or "intended
to be used"; and the word "shall" is mandatory and is not optional.