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:       Watch out ! You're too close to the fire place . 
 Person2:Don't worry , but my clothes are made of leathers . 
 Person1:        Really ? That's wonderful ! 
 Person2:Thank you for your warning . 
 Person1:        Not at all . 
 Person2:Be careful of yourself . 

informal