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:       Merry Christmas !  
 Person2:Huh ?  
 Person1:        I said Merry Christmas ! Don't you know that Christmas is almost here ?  
 Person2:It is ? Oh , that's nice .  
 Person1:        Huh ? Didn't you know ? Aren't you excited ?  
 Person2:Actually , I'd forgotten about it .  
 Person1:        Forgotten about it ? How could you ?  
 Person2:Because I'm not Christian , I'm Jewish .  
 Person1:        Oh , I'm sorry . I didn't know .  
 Person2:It's all right . There are so many Christians in America that everybody takes it for granted that I'm Christian .  
 Person1:        I guess so . So what do you do around this time of year ?  
 Person2:Well , I'll celebrate Hanukah soon , but that's not as important to us as Christmas is to you . Mainly I'll just enjoy the holiday break .  
 Person1:        Well , would you be horribly offended if I invited you to a Christmas party at my house ?  
 Person2:Not at all . A party is a party . I'll be happy to come . 

informal