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:       Harry was angry last night . 
 Person2:That's because he's getting nervous . Anyway , this is the first time he's directed a play . 
 Person1:        But he used to be very relaxed and cheerful . It's not like Harry to do a thing like that . 
 Person2:Yes , you're right . Maybe there's any other reason . 

informal