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 , what ’ re you reading ?  
 Person2:Oh , it ’ s Death on the Nile . Have you read it ?  
 Person1:        No , not that one . But I saw the movie . Could I borrow it when you finished .  
 Person2:Sure . I didn ’ t know you liked mysteries .  
 Person1:        Oh , I ’ m crazy about them . 

informal