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:       My goodness ! What happened ? You have blood on your face .  
 Person2:Oh , don't worry . I just killed a pigeon .  
 Person1:        How could you have the heart to kill it ? We only have one !  
 Person2:It spoiled my painting ! 

informal