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: Can we go to the beach on foot ?
Person2:Oh , it's too far to walk there.We can take a bus .
Person1: Is the bus station close by ?
Person2:Yeah , it's a block away down the street .
Example Output: formal

Example Input: Person1: All right . But these are black and I don ' t like black shoes . They ' re dull .
Person2:Well , black is a better color than pink . Pink ' s for girls .
Person1: Then why are you wearing black shoes ?
Person2:Because ... oh , all right . You win . Let ' s pay for them and go .
Person1: Hey , thanks , mum .
Example Output: informal

Example Input: Person1: Dear Anna . I really love you .
Person2:I love you , too .
Person1: I want to take care of you forever . Will you marry me ?
Person2:Oh . My God ! Are you serious ?
Person1: Am I too abrupt ? Did I scare you ? Or you don't want ...
Person2:No ! I have been expecting this moment for a long time . I mean my answer is ' yes ' .
Person1: Oh , I'm so happy . I will try my best to love you and protect you . I promise .
Person2:I trust you . We'll be happy .
Person1: Let me wear you this diamond ring .
Person2:It's so beautiful .
Example Output:
informal