ALTERNATE=[LEFT|RIGHT|TOP|BOTTOM]

      Shifts every other page image in preparation for two-sided
      printing.  Use this option in combination with the MARGINS
      option.

      Specify one of the words, LEFT, RIGHT, TOP or BOTTOM to
      cause the DECprint Supervisor to shift alternate page side
      images appropriately.  Specifying LEFT or RIGHT alternates
      the left and right margins you specify with the MARGINS
      option (those margins along the long edge of a sheet of
      paper).  Specifying TOP or BOTTOM alternates the top and
      bottom margins you specify.

      If you specify ALTERNATE with no option values, left and
      right margins alternate.