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:       Tyler residence .  
 Person2:Is this Naomi ?  
 Person1:        No , this is her sister , Nancy .  
 Person2:You sure sound like Naomi .  
 Person1:        Oh . Can I take a message ?  
 Person2:Sure . Please tell her that Andy called .  
 Person1:        Okay . I'll give her the message .  
 Person2:Thanks .  
 Person1:        Bye . 

informal