Insertar varias filas en la tabla:obtener el error ORA-00933:el comando SQL no finalizó correctamente

Sintaxis incorrecta.

O bien

insert into employee (employee_id, last_name, salary)
  values (129, 'khaj', 19000);
insert into employee (employee_id, last_name, salary)
  values (130, 'ravi', 20000);

o

insert into employee (employee_id, last_name, salary)
  select 129, 'khaj', 19000 from dual union all
  select 130, 'ravi', 20000 from dual;

o incluso

insert all
  into employee (employee_id, last_name, salary) values (129, 'khaj', 19000)
  into employee (employee_id, last_name, salary) values (130, 'ravi', 20000)
select * from dual;