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:       Mary , today is a great day for you . 
 Person2:How nice of you to remember ! 
 Person1:        Oh , here's a little token of my affection . 
 Person2:You're so thoughtful.Thank you . 

informal