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:       I am sorry , but I can't stay until the end of class .  
 Person2:Where do you need to be that is more important than school ?  
 Person1:        I have an appointment .  
 Person2:Do you have a plan to make up your missed work ?  
 Person1:        No , but I'll make sure someone helps me out this week with my missed work .  
 Person2:Are you going to go right away ?  
 Person1:        I am leaving right now .  
 Person2:All right , but please remember that it is your responsibility to catch up .  
 Person1:        Thanks , Professor . I'll make sure everything gets taken care of .  
 Person2:Goodbye , and try not to miss any more school . 

formal