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:       Do you like climbing ?  
 Person2:Yes , I like it very much .  
 Person1:        How about climbing up the Fragrant Mountain tomorrow ?  
 Person2:Where is it ?  
 Person1:        It is located at the east foot of Western Mountain of Beijing , in a park with the same name . There are some huge stones within the mountain which look like the censer , so it is called ' Fragrant Mountain ' .  
 Person2:Have you visited it before ?  
 Person1:        Many times . Except climbing , there are many attractions worth visiting .  
 Person2:Like what ?  
 Person1:        It is the best season to view red leaves from the Mid-October to the first ten days of November . During the period , thousands of hectares of maples on the sloping field are so red that you would recognize them as fallen petals by mistake if looking from a further area . The bright red , pink , scarlet , and peach-puff leaves are distributed in different layout , with some green pines and cypresses dotted in between .  
 Person2:Sounds marvelous .  
 Person1:        You can take a bird-eye view at the glorious picture when you arrive at the top of the mountain .  
 Person2:Great . I will prepare some clothes and food for the climbing . 

informal