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:       Does your girl friend like swimming ?  
 Person2:Yes , she does . She is good at backstroke and free style .  
 Person1:        Then you can help her with the breaststroke and sidestroke .  
 Person2:But she wants to learn the butterfly stroke  
 Person1:        Really ? Then just ask her to follow me .  
 Person2:I heard you are now practicing underwater swimming , aren't you ?  
 Person1:        Yes . But I still have some difficulties it breathing .  
 Person2:Say , kid , keep on practicing , you're sure to be a first-class swimmer .  
 Person1:        To tell you the truth , I have never thought of being a swimmer . I swim just for fun .  
 Person2:That's good . 

informal