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:       Why do you stop me ?  
 Person2:You have gone against the traffic rules .  
 Person1:        I'm sorry .  
 Person2:Do you know this is a Onaway street ?  
 Person1:        I don't know .  
 Person2:You have to pay a fine . 

informal