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:       Do you know which stop we get off at ? 
 Person2:We still have more to go , I think . 
 Person1:        We've been on this bus for a while now . 
 Person2:You're right . 
 Person1:        Should we have gotten off the bus already ? 
 Person2:I don't think so . 
 Person1:        I thought you knew . 
 Person2:Maybe we did miss our stop . 
 Person1:        Really ? 
 Person2:I'm positive that we missed our stop . 
 Person1:        I'm never catching the bus with you again . 
 Person2:My mistake . 

informal