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:       Well , what about it ? As it happens I've got two tickets for next thursday evening . I thought perhaps .  
 Person2:Well , thanks all the same , Denise . But no I don't think.Sorry , I'm sure you would enjoy it . I'd like to Denise , but I'm busy on friday this week and next week too .  
 Person1:        But I said thursday.The tickets are for thursday evening .  
 Person2:Thursday ? Oh , sorry . I meant thursday too . I mean I busy then too .  
 Person1:        I see.Oh , well some other time perhaps .  
 Person2:Yes . some other time perhaps.Thanks again . 

formal