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 is a new restaurant opening up in town next month . 
 Person2:What kind of food will they be serving ? 
 Person1:        My favorite , Mexican . And I've heard that the head chef is from San Paulo . 
 Person2:It sounds like this is going to be authentic Mexican food . 
 Person1:        I can hardly wait ! 
 Person2:Do you know the day they plan to open ? 
 Person1:        I'll double check the announcement . 
 Person2:Maybe we can make reservations ahead of time ? 

informal