display the emails of the employees who have no commission percentage and salary within the range 7000 to 12000 and works in that department which number is 50.
return employees ;return #1 who  have commission percentages ;return #1 besides  #2 ;return salaries of #3 ;return #3 where #4 is at least 7000 ;return #3 where #4 is at most 12000 ;return #3 in  both #5 and  #6 ;return departments of #7 ;return department number of #8 ;return #7 where #9 is equal to 50 ;return emails of #10
['select', 'filter', 'discard', 'project', 'comparative', 'comparative', 'intersection', 'project', 'aggregate', 'comparative', 'project']