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:       Who wants to go first ? Allen ? 
 Person2:Uh ... I mostly just like to listen . You're the groom . Why don't you go first ? 
 Person1:        OK . Put on something by the Backstreet Boys ! 
 Person2:How about As long as You Love Me ! You can pretend you're singing it to your fiancee Brooke ! 
 Person1:        I'd better not . Brooke hates the Backstreet Boys ! 

informal