question: What are the names, countries, and ages for every singer in descending order of age?
#1 return singers 
#2 return the  names of  every #1 
#3 return the  countries of  every #1 
#4 return the  ages of  every #1 
#5 return #2 ,  #3 ,   #4 
#6 return #5 sorted by descending order of  #4