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:       Look , it's all water over the dam now . Let's leave it behind us .  
 Person2:Yeah , I know , but it's too hard to do .  
 Person1:        Our eyes should look into the future . We could not live in the past .  
 Person2:Only sometimes when I think about it , I feel very sad .  
 Person1:        It's normal . Time will change everything . 

informal