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:       John , if you don't mind , I'd like to ask you a personal question .  
 Person2:I don't mind at all .  
 Person1:        All right.Are you married ?  
 Person2:To tell you the truth , I'm not married . I'm still single .  
 Person1:        Then , when do you plan to get married ?  
 Person2:I don't know.It ' s still up in tha air . 

formal