You must specify at least one qualifier.

    The EXPAND command moves one or more display-window borders
    according to the qualifiers specified (/UP:[n], /DOWN:[n],
    RIGHT:[n], /LEFT:[n]).

    The EXPAND command does not affect the order of a display on
    the display pasteboard. Depending on the relative order of
    displays, the EXPAND command can cause the specified display to
    hide or uncover another display or be hidden by another display,
    partially or totally.

    Except for the PROMPT display, any display can be contracted to
    the point where it disappears (at which point it is marked as
    "removed"). It can then be expanded from that point. Contracting
    a display to the point where it disappears causes it to lose any
    attributes that were selected for it. The PROMPT display cannot
    be contracted or expanded horizontally but can be contracted
    vertically to a height of 2 lines.

    A window border can be expanded only up to the edge of the
    screen. The left and top window borders cannot be expanded beyond
    the left and top edges of the display, respectively. The right
    border can be expanded up to 255 columns from the left display
    edge. The bottom border of a source or instruction display can
    be expanded down only to the bottom edge of the display (to the
    end of the source module or routine's instructions). A register
    display cannot be expanded beyond its full size.

    For a list of the key definitions associated with the EXPAND
    command, type Help Keypad_Definitions_CI. Also, use the SHOW KEY
    command to determine the current key definitions.

    Related commands:

       DISPLAY
       MOVE
       SELECT/SCROLL
       (SET,SHOW) TERMINAL