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:       Thomas , could you do me a favor ?  
 Person2:What's up ?  
 Person1:        Could you pick up Mrs . David from Ford Company at the Capital Airport ?  
 Person2:Why don't you go ?  
 Person1:        I'm supposed to do it , but the general manager called me last night . He said he couldn ’ t come back to Beijing as scheduled , so he asked me to attend the meeting for him .  
 Person2:I see . I'll do it for you .  
 Person1:        Thanks a lot . It ’ s very kind of you . 

informal