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'.

Example Input: Person1: What do you think of your teacher ?
Person2:He's very strict with us .
Person1: And I hear he gives very good lectures .
Person2:Indeed . He's strict with himself , too . We can see every lecture of his is well-prepared .
Example Output: informal

Example Input: Person1: Here ' s a letter for you .
Person2:Let me see it .
Person1: Who ' s the letter from ?
Person2:It ' s a letter from UCLA about my acceptance .
Person1: Read it !
Person2:UCLA accepted me !
Person1: Really ?
Person2:I ' m not joking . I got accepted !
Person1: I ' m so happy for you !
Person2:UCLA was my second choice , but I ' m happy knowing I ' Ve been accepted .
Person1: I am really proud of you .
Person2:You have no idea how proud I am of myself .
Example Output: informal

Example Input: Person1: Excuse me . Is this seat taken ?
Person2:No , it isn't .
Person1: Am I on right bus to Chicago ?
Person2:Oh , no . This is going in the opposite direction .
Person1: Oh , my God !
Person2:I suggest you get off at the next stop and ask again at the station .
Person1: I will . Thank you .
Example Output:
informal