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:       Good evening . Welcome to our program .  
 Person2:Thank you . Good evening , Mr.Dean .  
 Person1:        Would you tell us your name , please ?  
 Person2:I'm Helen Baker .  
 Person1:        Glad to meet you , Ms.Baker .  
 Person2:Glad to meet you , too .  
 Person1:        Where are you from , Ms.Baker ?  
 Person2:I'm from New Zealand .  
 Person1:        What do you do for a living ?  
 Person2:I'm a teacher .  
 Person1:        Thank you for coming , Ms.baker . 

informal