source$ = "Hello, world!"

      REM Copy the contents of a string:
      copy$ = source$
      PRINT copy$

      REM Make an additional reference to a string:
      !^same$ = !^source$
      ?(^same$+4) = ?(^source$+4)
      ?(^same$+5) = ?(^source$+5)
      PRINT same$