How revoke privileges from user ?

 Hi all,

   I created a TEST user and have been used it to kill session and alter user. And I grant some privileges to it success ! My db server has another schema with name is PRODUCT. And when I try use TEST user to select and insert some tables that belong to PRODUCT --> TEST can do this ? But I did not grant INSERT and SELECT privileges to TEST !

   After created TEST user, I grant some privileges to TEST such as:

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grant connect, oem_monitor to TEST;

GRANT EXECUTE ON SYS.kill_session to  TEST ;

GRANT SELECT ON V_$SESSION  TO  TEST ;