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:       Merry Christmas , Linda !  
 Person2:Merry Christmas , Lee !  
 Person1:        Linda , thank you for this wonderful Christmas dinner . I really enjoyed it .  
 Person2:Thank you for coming . I'm glad you liked it . 

informal