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:       Hi , Kenji .  
 Person2:Hi , Debbie . Have a seat . How's it going ?  
 Person1:        I'm OK . How are you doing ?  
 Person2:Pretty good . Listen ... have you heard about the new Thai restaurant over on University Avenue ?  
 Person1:        Do you mean The Bangkok ?  
 Person2:That's the one . A bunch of us are going there for dinner tomorrow night.How about coming with us ?  
 Person1:        Sure , I'd love to .  
 Person2:Great . I'll call and make reservations .  
 Person1:        Any time after 6 o'clock is good for me.Oh ! I'm late ! I have a class .  
 Person2:All right . I'll call you tonight and tell you the time .  
 Person1:        Great . Talk to you then . 

informal