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 .  
 Person2:Now . you can see why it's called the Lantern Festival .  
 Person1:        Yes , it deserves its name .  
 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:        It's interesting and I want to buy one home . 

informal