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 want to check in now . Here is my ticket .  
 Person2:Don't you have any luggage to check in ?  
 Person1:        No , sir .  
 Person2:Do you have a seat preference ?  
 Person1:        I'd like an aisle seat . I feel terrible near the window .  
 Person2:Here is your boarding pass . Have a nice day . 

formal