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:       Where is the bus ? 
 Person2:I think it's running late . 
 Person1:        It should've been here 30 minutes ago . 
 Person2:It should be coming soon . 
 Person1:        It better , because I'm already late for work . 
 Person2:I can't stand riding the bus . 
 Person1:        Me too , it's so unreliable . 
 Person2:That is true . 
 Person1:        It's also horrible having to be at a bus stop in any kind of weather . 
 Person2:Exactly.That ' s the worst part . 
 Person1:        I think it's time we started driving . 
 Person2:Yes , I agree . 

informal