Task: Question Generation
Input (English): #1 return Ivan  took control of the  disputed territory in  1577 
#2 return the  Commonwealth did win a favorable treaty from  Ivan  
#3 return year of #1 
#4 return year of #2 
#5 return difference of #3 and  #4
Output (English): After Ivan took control of the disputed territory in 1577, how many years did it take the Commonwealth to win a favorable treaty from Ivan?