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:       Now that we know what kind of music we will play , we have to decide what each of us will do .  
 Person2:Well , I love hip hop dancing , so I should probably dance . Do you know how to rap ?  
 Person1:        Oh yeah ! I'm a great rapper . And I know all the Vanilla Ice lyrics by heart .  
 Person2:Excellent . I'll start practicing my dance moves . 

informal