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:       School has added several new courses to our grade this semester . I have more homework to do now .  
 Person2:What's your favorite course , Daniel ?  
 Person1:        I like science most .  
 Person2:Science ? That's a surprise .  
 Person1:        Surprise ?  
 Person2:I thought you would like PE .  
 Person1:        I do like PE , but I am interested in science .  
 Person2:Are you interested in science ? I can't believe it .  
 Person1:        Through this course , I can learn more about the world around us clearly .  
 Person2:Your parents would be happy if they knew that . Because you are always a naughty boy .  
 Person1:        Naughty ? I'm naughty ? I'm just clever . So I only do the things I am interested in .  
 Person2:Hope so . 

informal