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:       Hey , Taxi . Over here !  
 Person2:Did you call for a car service  
 Person1:        Yes , are you engaged  
 Person2:Not at the moment . Where would you like me to take you  
 Person1:        I am going to the airport , and I have to catch the 930 flight to New York .  
 Person2:Well , it's a long way and there is roadwork near Broadway . I am not sure I can snake it in half an hour .  
 Person1:        But I can't miss the flight . It's an important meeting and it ’ s waiting for me .  
 Person2:All right , I will try my best . If there aren ’ t any holdups , I think we can get there in time .  
 Person1:        That's great . How much is it to the airport  
 Person2:About $ 25 , tips not included .  
 Person1:        Fine . Will you please help me with the luggage  
 Person2:Oh , yes , sure . Let me put it in the boot .  
 Person1:        Thanks very much .  
 Person2:Not at all . Bang the door , please .  
 Person1:        Ok , let's hurry .  
 Person2:You are in luck . The traffic is not heavy today . 

informal