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:       There must be something weighing on your mind . What is it ? 
 Person2:Dad , I lost mum's necklace . I'm afraid she will scold me . 
 Person1:        Don ’ t worry . I'll buy a new necklace as same as the old one . 
 Person2:It is so kind of you , Dad . 

informal