What are the first and last name for those employees who works either in department 70 or 90?
return employees ;return departments of #1 ;return #1 where #2 is  70 ;return #1 where #2 is  90 ;return #3 ,  #4 ;return first names of #5 ;return last names of #5 ;return #6 ,  #7
['select', 'project', 'comparative', 'comparative', 'union', 'project', 'project', 'union']