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:       Daniel , have you ever heard about the wildlife sanctuary ?  
 Person2:Is that different from this kind of zoo ?  
 Person1:        Yes , of course .  
 Person2:So tell me about it !  
 Person1:        There are a lot of wild animals in that place , and also some special rules while visiting .  
 Person2:Special rules ?  
 Person1:        There , you only have two ways for visiting .  
 Person2:Details ?  
 Person1:        On their bus or in your own cars , and you won't be allowed to get off the bus until you reach the special region .  
 Person2:Why not ?  
 Person1:        Because it is dangerous to get out of the car or bus . You can just imagine how fierce the wild animals can be .  
 Person2:That makes sense . But that sounds interesting . Is there one in Beijing too ?  
 Person1:        Yes .  
 Person2:I prefer to go there next time .  
 Person1:        Yeah , sure , you won't be disappointed . 

formal