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:       Hey Mike . What are you doing tonight ? 
 Person2:Nothing planned . How about you ? 
 Person1:        Work is kicking my ass . I'm so stressed . Let's go grab a drink . 
 Person2:I'm always up for a drink . To tell you the truth , it's been quite stressful here too . 
 Person1:        I say we get drunk tonight . I don't want to think about all this stuff . 
 Person2:But we have to work tomorrow . 
 Person1:        We won't stay out too late . I just need to forget about work . 
 Person2:I hear ya . Let's do it . 

informal