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:       Alison , would you like to have some more ?  
 Person2:No thanks . I've had enough .  
 Person1:        Actually you haven't had much .  
 Person2:To tell you the truth , I am on the diet .  
 Person1:        That sounds ridiculous . Why ?  
 Person2:Well , I am gaining weight these days , and I have to watch my calories . 

informal