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:       Kevin ? Hi , it ’ s Elizabeth . I have a big favor to ask you .  
 Person2:How big , Elizabeth ? Last time you said that , I ended up working overtime 3 nights in a row !  
 Person1:        Well , I ’ Ve got a huge load of typing and Mr . Blake has insisted I get it done by tomorrow afternoon .  
 Person2:All right , Elizabeth . But this is the last time . 

formal