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:       My goodness.She is thirty seconds faster than the world records in five thousand meters race . 
 Person2:Excuse me.What did you say ? 
 Person1:        A chinese girl have broken the world record in the Olympic Games 
 Person2:That's incredible . I cann't believe it . 
 Person1:        You have to . It's sure . 
 Person2:How amazing ! 

informal