DECLARE
type tablesarray IS VARRAY(11) OF VARCHAR2(40);
tablesList tablesarray;
total integer;
BEGIN
   -- Insert your tables here:
   tablesList := tablesarray('Table1', 'Table2', 'TableX');
   total := tablesList.count;
   -- Replaces SCHEMA and User:
   FOR i in 1 .. total LOOP
      EXECUTE IMMEDIATE 'grant insert, update, delete on SCHEMA.' || tablesList(i) || ' to USER';
   END LOOP;
END;
/