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:       Hello Mei , How about going for a meal this evening ?  
 Person2:Good idea ! I finish work at five . Why don ’ t we meet at six ?  
 Person1:        Ok that sounds good . Where shall I meet you ?  
 Person2:Let ’ s meet in front of the train station .  
 Person1:        Ok great , I ’ ll see you at six .  
 Person2:Ok , see you tonight ! Don ’ t be late ! 

informal