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:       What a busy week ! 
 Person2:Really ! I've never seen so much work . 
 Person1:        Right.How are you going to spend your weekend ? 
 Person2:I don't know . I have no idea . 
 Person1:        Would you like to play some tennis with me before going home ? 
 Person2:I'm not good at sports , I have never played tennis , and I know I would be terrible . 
 Person1:        You should try it.It ' s a great game . Come on , let me help you . I'm a good player , and a good teacher , too.What do you say ? 
 Person2:OK , but don't say I didn't warn you . 
 Person1:        That was a pretty good shot , Mary . 
 Person2:Thanks.This is fun ! 
 Person1:        Let me help you with your serve . 
 Person2:No one has ever tried to show me how to play a sport before.Maybe I should learn to do something . 
 Person1:        Of course , you can.All you need is a little help and a lot of practice . 
 Person2:Do you really think I can be a good player ? 
 Person1:        Well , maybe not a Michael Zhang , but better than the average . Person would you like to play again Wednesday ? 
 Person2:Yes . This has been fun . 

informal