GRANT execute on sys.dbms_sql TO system with admin option;

[KenEwald]

The error text below implies that you're missing a ";" on the prior statement in your script.

Error: ORA 993
Text: missing GRANT keyword
-------------------------------------------------------------------------------
Cause: The keyword WITH was specified at the end of a GRANT statement without
the keyword GRANT.
To grant privileges to a user and the permission to grant those
privileges to another user, you must specify the keywords WITH GRANT
OPTION at the end of the GRANT statement.
Action: Change the keyword WITH to the keywords WITH GRANT OPTION, then retry
the statement.
.