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:       How could you have done that without asking me first ? 
 Person2:I didn't realize you felt so strongly about it . 
 Person1:        Well , you should have thought . 
 Person2:I'm sorry . I'll ask next time . 

informal