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 singing ?  
 Person2:Yes , I do .  
 Person1:        Let's go to a ETV tonight .  
 Person2:But I can't sing it well .  
 Person1:        It doesn't matter . No one will laugh at you .  
 Person2:OK , I'Il go with you . When shall we go ?  
 Person1:        What about six ?  
 Person2:It's too early . Let's make it seven , OK ?  
 Person1:        OK . Let's make it . 

informal