Find the names of all procedures such that the cost is less than 5000 and physician John Wen was trained in.
return procedures ;return cost of  #1 ;return #1 where  #2 is  lower than 5000 ;return physician trained in #1 ;return #1 where  #4 is  John Wen ;return #1 of  both #3 and #5 ;return names of  #6
['select', 'project', 'comparative', 'project', 'comparative', 'intersection', 'project']