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:       What can I do for you , sir ?  
 Person2:I'd like to choose one game for myself and one for my younger sister .  
 Person1:        What kind of games do you like ?  
 Person2:Big games of course .  
 Person1:        I see , but games are played in different ways . I'm wondering what type of games do you like to play ?  
 Person2:Type ? I don't know , what do you have ?  
 Person1:        Basically , there are 7 types of games  
 Person2:Well , I am a beginner . I ...  
 Person1:        Don't worry . Most male customers choose first person shooting , real time strategy , action or sports , while female customers prefer simulating , action or role playing . Shooting , action and sports games require flexible movements and real time strategy usually needs overall consideration .  
 Person2:I like first person shooting and action more than other types of games .  
 Person1:        If so , counter Strike and Might & Magic are good alternatives . Counter Strike is one of the hottest shooting games and Might & Magic series are popular among girls because the game has attractive plot and interesting scenes .  
 Person2:Oh , thanks a lot . Then , I will take the two .  
 Person1:        Do you want the latest editions ? If your computer runs fast , I think the latest editions are better because although old editions are cheaper , they are less exciting and attractive .  
 Person2:I will have the latest editions . 

informal