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:       That's a very nice pair of glasses .  
 Person2:Does it really look OK ?  
 Person1:        Yes , and I like the color too . It matches your eyes .  
 Person2:And I got it on sale .  
 Person1:        That's incredible ! 

informal