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:       Are you ready to go shopping ? 
 Person2:Not yet . I'm not finished with my research yet . 
 Person1:        What research ? 
 Person2:Reading my fashion magazines ! How do you think I know so much about all the latest trends ? 
 Person1:        But they're just ads ... 
 Person2:Duh ... That's the point . The people in the ads are wearing what's in . Plus , there are articles on new trends ... 

formal