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:       Rachel has decided to quit smoking .  
 Person2:Really ? Why ?  
 Person1:        You never guess she is going to have a baby .  
 Person2:Oh , it's unbelievable . She is such a chain smoker .  
 Person1:        Yes , yes . She said she is going to stop drinking coffee too and quit all the unhealthy habits just for the baby .  
 Person2:Oh , she is going to be a great mother . 

informal