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:       Hi , Bill . I saw you yesterday with a pretty girl .  
 Person2:Yes , she is my favorite girl . I've decided to go steady with her .  
 Person1:        Are you sure she is the right girl ?  
 Person2:Sure . She is the ideal girl , the one I had dreamed of .  
 Person1:        What type of girl is she ?  
 Person2:She is the mature , stable , feminine type . I hope one day I can marry her .  
 Person1:        Oh , that's great . You're serious this time . 

informal