question: How many years had passed from when the Yunnan government reported the news to the Emperor until a Burmese army was increasing its grip of the borderlands?
#1 return the  Yunnan government reported the   news to the    Emperor 
#2 return a Burmese army was  increasing its grip of the  borderlands 
#3 return year of #1 
#4 return year of #2 
#5 return difference of #4 and  #3