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:       What do people usually do on Saint Valentine's Day ?  
 Person2:On that day , boys are supposed to give roses to their sweethearts .  
 Person1:        What will the girls do ?  
 Person2:They give chocolate in return . 

formal