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:       How time flies !  
 Person2:May and Danny have already grown up .  
 Person1:        I can still remember our first date .  
 Person2:Look at that big tree over there .  
 Person1:        Yeah , oh my god ! It's still there . We have our first date right on there .  
 Person2:Do you know that I fell in love with you at the first sight .  
 Person1:        You were dull at that time .  
 Person2:But you agreed to go out with me at last .  
 Person1:        I can't believe this for it's been 20 years since we got married . 

informal