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:       I have never experienced a roller coaster . I want you to sit beside me .  
 Person2:Wait a moment , I want to go to the toilet .  
 Person1:        You try to put on a brave face . 

informal