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:       There is a wonderful opera today . I'd like to see it . 
 Person2:I do not like the play with complicated plot . What's on today ? 
 Person1:        ' The sound of music ' . This music is known by everybody and is suitable for all ages . It is about a happy family without sex , violence or bad language . 
 Person2:I know that . I have seen the film as the same title . Andrews gives a performance to be remembered for a lifetime from Maria to a cheerful governess . 
 Person1:        Yes , you are right . I like the song in the movie , edelweiss , do you remember it ? 
 Person2:Of course , it is a nice song that can make audience calm and pleasant . 
 Person1:        Those young actors play the roles perfectly . 
 Person2:I hope the opera will be more stupendous than the movie . Have you bought the tickets ? 
 Person1:        No , I am asking you whether you will go to see it . 
 Person2:Let's go . We'd better buy the tickets earlier and have dinner in restaurant . 

informal