Definition: You are given a conversation between two people. 'Person1:' and 'Person2:' are used to separate their respective dialogues. You are required to assign a label 'formal' if there is an absence of emotion and a presence of questions anywhere within the conversation. If such pattern is not found assign the label 'informal'.
Input:  Person1:       How many people are there in your family ?  
 Person2:Five . Besides my parents and me , there are my brother and sister .  
 Person1:        That ’ s a big family . How old is your brother ?  
 Person2:Eighteen .  
 Person1:        What about your sister ?  
 Person2:She ’ s not quite twenty-five .  
 Person1:        Do you miss your family ?  
 Person2:Yes .  
 Person1:        Do you often go home ?  
 Person2:No . But I often send e-mail to them . And make a call to my parents regularly .  
 Person1:        How often do you call to them ?  
 Person2:Once a week . 

formal