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:       Ok , so who are we going to invite to our dinner party ? 
 Person2:Well , we have the Thompsons , the Greens , and the Anderson , about twelve people total . 
 Person1:        Don't forget my friend Andy from the office . He has nothing to do on Friday , so I invited him over . 
 Person2:But that makes thirteen people ! We can't have thirteen people for dinner on Friday ! 
 Person1:        Why can't we ? 
 Person2:It's an old superstition . If we have thirteen people at the table , then it means bad luck . Can Andy bring a date ? 
 Person1:        I'm not sure . He just broke up with his girlfriend recently , and I don't think he's in the mood to start again so soon . 
 Person2:But we can't have thirteen for dinner ! 
 Person1:        I think you're making a mountain out of a molehill . It's only a superstition . It really doesn't mean anything . 
 Person2:Absolutely not ! I refuse to have thirteen people for dinner on Friday ! 
 Person1:        Ok , ok . I'll ask my sister to come . That way we'll have fourteen for dinner . 
 Person2:That's better . 

informal