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:       Tomorrow is Sunday . Let's go out and get some fresh air . 
 Person2:I know there is a beautiful farm in the countryside near Taipei . Are you interested in going there ? 
 Person1:        why not ? I love animals and I love nature . 
 Person2:You can see many cows and horses there . lf you are brave enough , you can try horseback riding . it is fun . 
 Person1:        sounds very interesting . I can't wait to go there . 
 Person2:Wow ! It is huge and you can do many activities here . 
 Person1:        That is true . Some people go camping , some people pick fresh fruit , some people go boating and some people go grass skiing . 
 Person2:I never knew there were so many fun things to do on a farm . 
 Person1:        Well , now you know . Let's go to the lake over there . Some people are fishing over there . I haven't had a chance to fish in a lake , I really want to try . 
 Person2:I think we need to buy some baits and borrow some fish poles first . 
 Person1:        Yes . we can get what we need at the stands right by the lake . Who do you think will catch a big fish first ? 
 Person2:Of course . I will . 
 Person1:        Wait and see . I want to try horseback riding after fishing . It looks very exciting and fun . 
 Person2:It is . However , you will suffer from muscle pain for many days you are a first-time rider . 
 Person1:        No problem . It is always worth trying something new once in your life time . 

informal