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:       Please help yourself to whatever you like , don't be shy . 
 Person2:Yes , thank you . I ’ Ve already been helping myself . 
 Person1:        This dish tastes terrific . Would you like to try a little ? It is a little hot , but very good . 
 Person2:I like hot food , especially Sichuan cuisine . 
 Person1:        Would you like another beer ? 
 Person2:I'II have another cup of beer insist . I know I don't like to drink alone , especially there are someone sitting there next to me . 
 Person1:        Come on , it's the weekend . Let's taste and enjoy this meal . Cheers ! 
 Person2:Bottom's up , and you're right . This meal is incredible . I wish I had known this restaurant before . Thanks for bringing me here . I know I'll be back soon . 

informal