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:       Mike , what are you doing tonight ? 
 Person2:Nothing special . I just want to get plastered . 
 Person1:        I don't feel like drinking tonight . I'm gonna hang out at YY's . 
 Person2:YY's ? That place is boring . How about Xara's ? It's real classy , and they keep the place spin and span . 
 Person1:        Yeah , but it's expensive . Nah , I'm going to YY's . 
 Person2:On second thought , I think I'll join you . 
 Person1:        They ' Ve just renovated the place . You may be surprised . 
 Person2:Wow , they really went to town on this place ! 
 Person1:        Quite a difference , huh ? 
 Person2:Sure is . Waiter , bring us two drafts , please . 
 Person1:        Ah hah.Thought you were't drinking . 
 Person2:When in Rome , do as the Romans do . 

informal