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:       Hello , this is the International Student Office . My name is Leah . How may I help you ?  
 Person2:I'd like to speak to the Ms . Collins , please .  
 Person1:        Ok . Can I ask who is calling , please ?  
 Person2:This is Nathaniel Brown .  
 Person1:        And what is your call regarding ?  
 Person2:I'd like to talk to her about my accommodation situation .  
 Person1:        Ok , I'll try and put you through . Please hold .  
 Person2:Ok .  
 Person1:        ... Sorry , her line is busy at the moment . Can I take a message ?  
 Person2:Sure . Can you have her call me back on my cell phone number ?  
 Person1:        Ok . What's your number ?  
 Person2:It's 0-7- 7-8- 7-3- 6-7- 6-8- 8 .  
 Person1:        Let me repeat that back to you . That's zero , double seven , eight , seven , three , six , seven , double six , double eight .  
 Person2:No , there's no double six at the end of the number . It's just zero , double seven , eight , seven , three , six , seven , six , double eight .  
 Person1:        I got it . When should I have her call you back ?  
 Person2:Anytime before 6 pm tonight .  
 Person1:        Ok , Nathaniel . I'll have Ms . Collins call you back sometime tonight before 6 pm .  
 Person2:Thank you !  
 Person1:        Bye !  
 Person2:bye ! 

informal