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:       Are you ready to go the concert ?  
 Person2:Yes . Should we go there by bus so we aren't late ?  
 Person1:        Actually , why don't we go there by bike ? We could get stuck in traffic if we travel by bus in rush hour .  
 Person2:That's true . Cycling is good for our environment , too . Let me just get my helmet then .  
 Person1:        Is your helmet comfortable ?  
 Person2:Not really , but I liked the design , so I got it .  
 Person1:        Maybe you should think about getting a round helmet ; they're better .  
 Person2:I'll think about it .  
 Person1:        Is that your new bicycle ?  
 Person2:Yes , my father gave it to me for my birthday . Do you like it ?  
 Person1:        It's the newest 10 speed cycling mountain bike . These are really expensive !  
 Person2:Nothing but the best from my dad . I like everything about it except for the brakes . They are a bit sticky .  
 Person1:        I can fix those for you . Is there anything else wrong with it ?  
 Person2:Well , my saddle is too low for me . Do you know how to change the height ?  
 Person1:        That's easy . It's important to have the saddle high enough so that your legs can extend fully when you are on your bicycle .  
 Person2:Is that why my knees have felt sore after every time I've ridden my bike ?  
 Person1:        It's possible . Give me a minute and I can fix these for you and then we can go . 

informal