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 long have you been living in New York ?  
 Person2:Oh , about two years now .  
 Person1:        Where do your parents live ?  
 Person2:They still live in Shanghai where I was born .  
 Person1:        Do you write or call them very much ?  
 Person2:Yes , I try to keep in touch with them . 

formal