Substitution    Name                  Outputs
%s              subjective            he, she, it, or name
%n              name                  name
%p              possessive            his, her, its, or name's
%a              absolute possessive   his, hers, its, or name's
%o              objective             him, her, it, or name name
%r              reflexive             himself, herself, itself, or name
%l              location              [the name of the player's location]
%%              percent sign          %
%c              carriage return       [produces a newline]
%4 - %7         arguments             [the arguments given to the exit]
%0 - %3         lowercased arguments  [the arguments given, all in lower case]
%#              player's dbref        [the dbref of the player]
%!              thing's dbref         [the dbref of the exit/object]