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:       Do you like ice skating ?  
 Person2:I have never tried it .  
 Person1:        Then you've got to try it . Let's go to the skating rink on Thursday .  
 Person2:Sorry , I don't think I can .  
 Person1:        Friday then . How about it ?  
 Person2:Friday is great .  
 Person1:        It's settled then . 

formal