Task: Question Generation
Input (English): #1 return flights 
#2 return #1 from pittsburgh 
#3 return #2 to  baltimore 
#4 return #3 arriving on may seventh 
#5 return #4 that  are available 
#6 return aircraft of #5 
#7 return size of #6 
#8 return #6 where #7 is  the  smallest
Output (English): what is the smallest aircraft available flying from pittsburgh to baltimore arriving on may seventh