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:       Dear Anna . I really love you . 
 Person2:I love you , too . 
 Person1:        I want to take care of you forever . Will you marry me ? 
 Person2:Oh . My God ! Are you serious ? 
 Person1:        Am I too abrupt ? Did I scare you ? Or you don't want ... 
 Person2:No ! I have been expecting this moment for a long time . I mean my answer is ' yes ' . 
 Person1:        Oh , I'm so happy . I will try my best to love you and protect you . I promise . 
 Person2:I trust you . We'll be happy . 
 Person1:        Let me wear you this diamond ring . 
 Person2:It's so beautiful . 

informal