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 certain I am going to fail my English test .  
 Person2:Why are you so pessimistic ?  
 Person1:        Because it's impossible to improve listening level within a week .  
 Person2:Only for this reason ?  
 Person1:        Yes , I think my vocabulary and reading comprehension are not very bad .  
 Person2:Don't worry about it . Practice makes perfect . I will lend you some listening materials , so that you can practise more before the exam . I believe you can pass the exam with good preparation .  
 Person1:        Oh , thank you . That's very nice of you . 

informal