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:       Bobby ! Come here , look what I got you !  
 Person2:What is that ?  
 Person1:        A chess board ! Daddy is going to teach you how to play !  
 Person2:Cool !  
 Person1:        Ok , each player gets 16 pieces . You can be the white ones and I ’ ll play with the black pieces . Now in the front , you set up the pawns . Those are the least valuable pieces and can only move one space forward . When you are about to capture another piece , it can move one space diagonally .  
 Person2:What about all these other pieces ?  
 Person1:        See this one that looks like a tower ? It ’ s called the rook . The one with the tall hat is called the bishop . See this little horsey ? This is called the knight , it ’ s a very important piece so it ’ s best to not let your opponent capture it .  
 Person2:And these two ? They are husband and wife ?  
 Person1:        That ’ s right ! That ’ s the queen and that ’ s the king . If the other player captures your king , he will say ” Check Mate ” and the game is over ! Doesn ’ t this sound fun ?  
 Person2:Nah ! This is boring ! I ’ m gonna go play Killer Zombies on my PlayStation ! 

informal