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:       Bill , how can you hear so happy today ?  
 Person2:Aha . I've read of my roommate . I made a move today .  
 Person1:        Really ? What was the matter ?  
 Person2:You knew Brain Locker ?  
 Person1:        Brain Locker ? No , I don't think so . What does he look like ?  
 Person2:Well , he's thin and tall . He has brown hair , a holt nose , green eyes and wearing glasses .  
 Person1:        Mm . I've seen him a couple of times , I think . 

informal