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 know what E-commerce is ? 
 Person2:Well , I'm not sure . Maybe it means we can buy something through the Internet . 
 Person1:        That's right 
 Person2:It must be very convenient and pretty quick . 
 Person1:        Sure , but you must have access to the Internet . 

informal