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 Yahoo Greetings , Edgar ?  
 Person2:Sure . It's a popular e-card website .  
 Person1:        Can you tell me how to send one on it ?  
 Person2:Okay . Did you get the Yahoo ID ?  
 Person1:        ID ? What's that ?  
 Person2:I mean , you must register first before you send a card .  
 Person1:        Oh . I see . But I have done it .  
 Person2:Ok . Choose the card which you like best , and fill in the following blanks with both your and your friend's names and e-mail addresses .  
 Person1:        Is that all ?  
 Person2:Don't forget to send .  
 Person1:        Oh . I see . Thanks . 

informal