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:       Professor , I will not be here for our next class meeting .  
 Person2:Is this absolutely necessary ?  
 Person1:        I tried to work something out , but I really do have to miss one class .  
 Person2:Will you be able to make up the work you missed ?  
 Person1:        I'm going to be doing a lot of extra reading .  
 Person2:Remember that I will only let you miss one class meeting per semester .  
 Person1:        Yes , I remember .  
 Person2:Could you e-mail me this week as a reminder ?  
 Person1:        Sure , no problem .  
 Person2:Make good use of that day off ; you'll only have one this semester ! 

formal