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:       Who is it ? 
 Person2:Supervisor . Open the door . 
 Person1:        Wait a sec . 
 Person2:What are you doing here ? 
 Person1:        We're watching a football match . What's the matter ? 
 Person2:Your neighbors complained that you were so noisy that they can't sleep . 
 Person1:        I'm sorry about this . 
 Person2:Please turn down the TV . And not another shout or I'll have to report you to the school administration . 
 Person1:        You can rest assured that we won't disturb others anymore . 

formal