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 hate to say goodbye , but it's late .  
 Person2:Can't you stay for a little bit longer , it's only 8 .  
 Person1:        I wish I could.But I'm afraid I can't . I've got some serious studying to do . I have to go .  
 Person2:OK.See you on Today .  
 Person1:        See you on Moday.Have a great weekend .  
 Person2:You too.Thanks for dropping in . 

informal