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:       Mary , set your alarm clock for seven tomorrow morning .  
 Person2:Why ?  
 Person1:        I'm going to take you to your school to register for classes .  
 Person2:That's right . I haven't done that yet .  
 Person1:        You can choose classes that you like at the school office .  
 Person2:Really ?  
 Person1:        Well , there are core courses and electives .  
 Person2:What do they mean ?  
 Person1:        Core courses are ones that you must take . Elective courses are ones that you get to choose for yourself . 

informal