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:       Hi . Are you new in this class ? 
 Person2:Yes , I am . I really don't know anyone . 
 Person1:        My name is Steven . What's your name ? 
 Person2:My name is Bill . How are your lessons going ? 
 Person1:        Very well . And my favorite subject is Chinese . 
 Person2:I prefer to learn English . In my opinion , English is easier than Chinese . 
 Person1:        I guess English has fewer characters . 
 Person2:You are right . 

formal