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:       Did everyone fill out their entry permits ?  
 Person2:Yes . The videographer has already started filming my parents trying to speak English with the flight attendants .  
 Person1:        Speaking of flight attendants , they keep smiling at me . I wonder why ...  
 Person2:It'll be the year 2000 ! The flight attendants are coming over here . They're carrying bottles of champagne !  
 Person1:        That's because it's time .  
 Person2:Time for what ?  
 Person1:        It's time to make our wedding wish come true ...  
 Person2:You mean get married now ? On the plane ?  
 Person1:        Why not ? I've got the rings ready .  
 Person2:I don't know what to say , Jack !  
 Person1:        Hopefully , you'll say " yes " ... 

informal