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:       What can I do for you ?  
 Person2:I am trying to find this book .  
 Person1:        What ’ s the problem ?  
 Person2:It doesn ’ t seem like this library has it .  
 Person1:        Have you checked the computer ?  
 Person2:I have already .  
 Person1:        What did it say ?  
 Person2:It says the book is on the shelf , but I didn ’ t find it there .  
 Person1:        I can always borrow the book from another library .  
 Person2:You can do that ?  
 Person1:        I ’ ll make the call and contact you when it gets in .  
 Person2:That ’ s fantastic . Thank you . 

informal