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:       Please show me that hat , please . 
 Person2:This one ? 
 Person1:        No , the one next to it . 
 Person2:The mirror is behind you , sir . 
 Person1:        Is this a furry hat ? 
 Person2:No , sir . It's a genuine bonnet . 
 Person1:        Are you sure ? 
 Person2:Yes , sir . 

formal