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:       Have you ever been to Japan ? I'm going in the fall . 
 Person2:Yeah , I've been there twice . 
 Person1:        Really ? Tell me about it . What's it like ? 
 Person2:Oh , it's fantastic . 
 Person1:        Where did you go ? 
 Person2:On my first trip I went to Tokyo , and on my second trip I visited Kyoto . 
 Person1:        What did you think of Tokyo ? 
 Person2:Very big and exciting , but very crowded , too . 
 Person1:        Yeah . I've seen pictures of the crowds ! 
 Person2:And the restaurant are excellent ... but they're kind of expensive . 
 Person1:        And how about Kyoto ? 
 Person2:Kyoto is lovely . It's full of beautiful old temples and gardens.It ' s a very historic city . 
 Person1:        How was the weather ? 
 Person2:I was in Tokyo in August , and it was really hot and humid . I went to Kyoto in October.It was hot and sunny , but there was no humidity . 
 Person1:        Sounds perfect . I can't wait ! 

informal