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:       Well , Peter , you have to do better than that next time , won't you ?  
 Person2:Have I really got to do those exams again , Dad ?  
 Person1:        Of course , you have . You must try harder this time .  
 Person2:And must I go back to school ?  
 Person1:        No , you needn't do that . You'd better get a part-time job somewhere and go to evening classes .  
 Person2:But Dad , I should be working full-time at my age . I'm nearly 17 .  
 Person1:        You ought to have worked harder then you wouldn't have failed your exams . You have to take a job and study .  
 Person2:What else I've got to do ? Join the army ?  
 Person1:        Who knows ! That might come to later . 

formal