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:       Hi , Natasha , how's life ?  
 Person2:Great . My family came to visit me .  
 Person1:        Oh , you must be very happy . How many people are there in your family ?  
 Person2:My immediate family is very large . It's my mother , my father , my two older brothers , my younger sister and me .  
 Person1:        I have a small family . They are my parents , my younger brother and me .  
 Person2:I thought you were the only child in the family . Didn't China practice the only-child policy in the early 1980s ?  
 Person1:        Yes , it did . But my parents are ethnic minority people . It's a preferential policy for an ethnic minority family to have two children .  
 Person2:Interesting . What do you think about families with only one child ?  
 Person1:        The child must feel very longly . My younger brother is 10 years younger than me . Before he was born , I used to be the only child and always dreamed that I would have a younger sister or brother one day .  
 Person2:Do you get along well with each other ?  
 Person1:        Yes , we are very close . He is 12 years old now and very smart . He always makes us laugh a lot .  
 Person2:You are very lucky to have such a nice family .  
 Person1:        Thank you . 

informal