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:       Look ! The girl is so beautiful and she is smiling at me . She is lovely .  
 Person2:I can't agree with you . She's pretty , but she always blows hot and cold .  
 Person1:        What makes you think so ?  
 Person2:She's my sister , you know . 

informal