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:       What's the matter with you , then ? You look miserable .  
 Person2:It's us .  
 Person1:        What do you mean by us ?  
 Person2:Well , we used to talk to each other before we were married.Remember ?  
 Person1:        What do you mean ? We're talking now , aren't we ?  
 Person2:Oh , yes , but we used to do so much together .  
 Person1:        Yes . I remember.But we never used to argue.You used to think I was wonderful.Where are you going ?  
 Person2:Back to live with my parents.That ' s something else I used to do before we were married.Remember ? 

formal