sign := *top* & 
[ HEAD pos,
  SPR *list*,
  COMPS *list* ].

pos := *top*.
noun := pos.
verb := pos.
det := pos.

phrase := sign &
[ ARGS *list* ].

word := sign &
[ ORTH string ].

;;;;;;;;;;;;;;;;;;;;;;;

string := *top*.

*list* := *top*.

*ne-list* := *list* &
 [ FIRST *top*,
   REST *list* ].

*null* := *list*.