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:       That ’ s really a let-down . 
 Person2:Yeah . He really does let me down . 
 Person1:        But that should not be the reason for you to lose heart . 
 Person2:I ’ m at the end of tether . I run out of ideas . 

informal