Task: Question Generation
Input (English): #1 return flights 
#2 return #1 that  are round trip 
#3 return #2 in first class 
#4 return #3 from boston 
#5 return #4 to  san francisco 
#6 return tickets of #5 
#7 return cost of #6
Output (English): how much does a first class ticket cost from boston to san francisco round trip