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 , Dora , I haven't seen you for a long time . Where have you been ?  
 Person2:I didn ’ t go anywhere . I stayed at home .  
 Person1:        What's up ? You look unhappy .  
 Person2:Nothing . I just feel very lonely in this city . I miss my family .  
 Person1:        Oh , I know . Sometimes I have the same feeling with you . But you'd better not be so emotional .  
 Person2:Can you stay and accompany me for a while ?  
 Person1:        Sure , no problem . You can call me any time you are alone from now on .  
 Person2:Thank you so much . You are so sweet .  
 Person1:        Not at all . We are friends . 

informal