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:       Have we met ? 
 Person2:I don't think so . Michael . 
 Person1:        Hello , Michael . My name's Shirley . Pleased to meet you . 
 Person2:Pleased to meet you , too , Shirley . So , what do you do ? 
 Person1:        I work in marketing . I'm a regional marketing manager for an IT company . Normally , I work out of Beijing , but I'm here on business . My friend Judy over there , she lives here and she invited me to this party . And you ? How about you ? 
 Person2:I live here . I was invited by George-he's the tall guy over there . He looks a bit drunk , actually ... 

informal