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:       Hello Mike ! Would you like a drink ?  
 Person2:No , thank you . I had too much to drink yesterday evening . I had a bad hangover this morning . My head felt terrible .  
 Person1:        Were you celebrating something ?  
 Person2:Yes . It was a friend ’ s birthday party . We drank all kinds of things-beer , wine and spirits . After midnight , we were even drinking cocktails !  
 Person1:        It ’ s a bad idea to drink a combination of alcoholic drinks . You should stick with one for the whole evening .  
 Person2:I know , but it was a celebration , you Kwon ? I don ’ t think I ’ Ve see you drunk .  
 Person1:        I usually only drink beer and I rarely drink more than a few pints .  
 Person2:You are a sensible drinker . Anyway , I ’ m not going to drink any alcohol this evening . I don ’ t ’ want another bad hangover .  
 Person1:        Let me buy you a soft drink then . How about a coke ?  
 Person2:Yeah . That ’ s a good idea . I heard that coke was first used as a medicine .  
 Person1:        Rally ? ... barman ! ... a large coke with ice and lemon , please ... thanks . Here ’ s the money .  
 Person2:Are you going to the wine tasting tomorrow ?  
 Person1:        Yes . I thought it might be interesting to learn a little about wine ...  
 Person2:... and taste a few ! There will be wines from several countries and an expert to give advice on which wines are good and which ones are not .  
 Person1:        Yes . I ’ m looking forward to it . 

informal