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:       Hi , Kate .  
 Person2:Hi , Don . What a surprise !  
 Person1:        Yeah , I saw someone walking like you , but I wasn ’ t sure . We haven ’ t seen each other for how long ? Almost three months ? But you look quite different now .  
 Person2:Have you noticed what has changed ?  
 Person1:        Oh , you look quite slender and more vivacious . What have you been taking ? Are you on a diet ?  
 Person2:Yes . I ’ m on a diet , but I ’ Ve not taken anything . I just eat less and exercise more . And it really worked in the past three months . I ’ Ve lost twelve pounds .  
 Person1:        Wow ! That ’ s great . I sincerely want to achieve my weight loss goals , but it ’ s difficult for me to keep up the exercise . Also you know , old habits are hard to break .  
 Person2:What kind of exercise do you think I do ? I just go to dance everyday after work . I ’ m taking an amateur dance class . I dance two hours everyday .  
 Person1:        Dance ? You only go dancing ? That ’ s not hard . I can do that .  
 Person2:Sure . Join my class next week . 

informal