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:       I don't know . I think you might be over the hill .  
 Person2:Well , if not gymnastics , then mountain biking .  
 Person1:        Mountain biking is an Olympic sport ?  
 Person2:Since 1996 it has been . And I bet I'd be pretty good at it . I ride my mountain bike to work almost every day . 

formal