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:       Mike , come and look at this painting of shrimp ! It is so simple yet so vivid !  
 Person2:Yeah . It is incredible ! Is it the work of Qi Bakshi ?  
 Person1:        Yes , it is . How do you know that ?  
 Person2:Well , Qi is famous all over the world , isn ’ t he ? Besides I am quite interested in Chinese painting .  
 Person1:        Cool ! What kind of Chinese painting do you prefer , free sketch or claborate-style painting ?  
 Person2:I prefer free sketch , especially the landscape paintings . I can always feel peace and harmony from those landscape paintings .  
 Person1:        That's true . Chinese art stresses the harmony between man and nature , which is an important part of China's traditional culture .  
 Person2:I love this art exhibition !  
 Person1:        So do I . Let ’ s go to other areas to see what they have got , shall we ?  
 Person2:OK . 

informal