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:       Are you doing anything tonight ?  
 Person2:No , nothing . Why ?  
 Person1:        Do you like western music ?  
 Person2:Yes , I do , very much .  
 Person1:        There ’ s a concert tonight . Would you like to go and listen to it ?  
 Person2:Oh , yes . I ’ d love to . 

informal