substitutions
Commands like @fail, @ofail, @success, and @osuccess set messages
to be displayed when a player fails or succeeds in manipulating an
object or exit. To make sense, these messages must contain the
correct pronouns. Use one of the substitutions in the place of a
pronoun, and the correct text will be inserted into the message
when it's displayed. If the substitutions are capitalized, the
output will also be capitalized.
Some functions let you set your own substitutions; to reference
them if their name is longer than one character, use %{braces}.
To see a list of all the available substitutions, type 'help subs-list'.