Task: Question Generation
Input (English): #1 return Riga was  captured by the  Red Army 
#2 return the  Latvian Socialist Soviet Republic was  officially proclaimed 
#3 return when  was  #1 
#4 return when  was  #2 
#5 return difference of #4 and  #3 in  days
Output (English): How many days after Riga was captured by the Red Army was the Latvian Socialist Soviet Republic officially proclaimed?