If both desks have a computer or monitor visible.
return desks ;return computer ;return monitor ;return #1 that have #2 visible ;return #1 that have #3 visible ;return #4 , #5 ;return number of  #6 ;return if  #7 is equal to  two
['select', 'select', 'select', 'filter', 'filter', 'union', 'aggregate', 'boolean']