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:       Wow , there are so many lanterns to appreciate . Now , I can see why it's called the Lantern Festival . It deserves its name .  
 Person2:Yeah . People always enjoy the lighted lanterns and the gala performances .  
 Person1:        What are they doing over there ? People keep on gathering there .  
 Person2:Did you notice the characters on the lanterns ?  
 Person1:        Sure . But you know that I can't read any Chinese characters . What do they say ?  
 Person2:They are puzzles . It's a tradition to solve the puzzles on the lanterns during the Lantern Festival .  
 Person1:        Very interesting . But I'm afraid we'd better do something else . Hey , look ! There is a huge lantern there . Let's get close to it .  
 Person2:It's really eye-catching . It's the biggest dragon lantern I've ever seen in all my life .  
 Person1:        Really ? Then I'm really lucky . Oh , it's spewing fireworks from its huge mouth .  
 Person2:Very impressive . It's made of glass which makes it even brighter .  
 Person1:        There are many Chinese characters on its body , too . What are they about ? Puzzles ?  
 Person2:Let me have a look . Oh , no . They are Chinese poems which describe this happy scene . 

informal