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:       Hello ?  
 Person2:Hi , David . You are very difficult to reach . I called several times . But I kept getting a busy signal . Is your phone out of order ?  
 Person1:        No , not out of order . But we seem to have a bad connection on the phone line . I can ’ t hear you clearly .  
 Person2:Ok . Let me call you later . Is that okay ?  
 Person1:        Sure . Thanks . 

informal