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:       Helen , you must be excited at going to America to study . 
 Person2:Yeah , I've been looking forward to it for ages . 
 Person1:        What do your classmates think of it ? 
 Person2:They give me a lot of congratulations . 
 Person1:        How long will you study there . 
 Person2:Oh , maybe three years . I will study and get the master degree first . Then I will decide whether I will stay there or come back . 
 Person1:        Which university will you go to ? 
 Person2:Chicago University . My major is Economics . 
 Person1:        Good luck ! 
 Person2:Thank you ! 

informal