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'.
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Question: Person1: T he nineteenth of June is my birthday . I'm planning to have a small party . Could you come ?
Person2:Happy birthday to you ! I'd really love to come , but I'm not sure right now . I'll try to make it.Thank you for your invitation .

Answer: informal

Question: Person1: Well , humans could never make something like that .
Person2:Those poor Egyptians slaves worked so hard and you want to give aliens all the credit !
Person1: Be a little more open-minded , Stu ! Don't believe everything you read in your history books !
Person2:OK , but don't believe everything you see on The X-files , either !
Person1: Speaking of The X-files , it's on right now !

Answer: informal

Question: Person1: Hello , reservation desk . How can I help you ?
Person2:I ' d like to book a room .
Person1: What kind of room would you like , Ma ' am ? We got single rooms , double rooms , standard rooms , suites and deluxe suites .
Person2:What ' s the rate for a standard room ?
Person1: $ 79 a night .
Person2:I ' d like a standard room .
Person1: What date would you check in , Ma ' am ?
Person2:December 23rd , please .
Person1: How long do you plan to stay ?
Person2:4 days .
Person1: Could you give me your name and phone number ?
Person2:Nancy Brown . My phone number ' s 709 678 5634 . Nancy Brown
Person1: Thanks . What time will you arrive ?
Person2:Around 3pm .
Person1: Very good . Your reservation confirmation number is NB13579 . Thank you for booking in our hotel . Can I help you with anything else today ?
Person2:No , that ' s it . Thank you very much .

Answer:
formal