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:       It gives me great pleasure to introduce Mr ... eh Mr ... 
 Person2:Miss ! 
 Person1:        Yeah ! May I introduce Mis ... eh ... Miss ... 
 Person2:My name is Jane Brown ! 
 Person1:        Oh yeah ! Would you please welcome ... Miss Jan Brown . 

informal