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: Oh , what a pleasant surprise ! Don't you remember me ?
Person2:Mr.Black , if I'm not mistaken .
Person1: Right ! Glad to see you here .
Person2:Pleased to see you.too .

Answer: informal

Question: Person1: William , do you like studying English ?
Person2:I like studying English , and I can read well , but speaking can be difficult .
Person1: It's not that bad . If you talk to your American friends every day , you'll learn quickly .
Person2:Can I ask you a question ?
Person1: Sure , what do you want to know ?
Person2:I have my book from class here . How do you say this word ?
Person1: Laptop .
Person2:Sorry , I don't understand . What does that mean ?
Person1: A laptop is a type of computer that you can carry with you . Do you understand ?
Person2:Yes , I think so . Can you say it again ?
Person1: Laptop .
Person2:Laptop . Did I pronounce that correctly ?
Person1: Yes , that's right . That's very good .
Person2:Thanks . And this word ? How do you pronounce this ?
Person1: That word is pronounced kitchen .
Person2:Thanks so much . You're a good teacher .
Person1: Thanks .

Answer: informal

Question: Person1: Jane , I was wondering if you you had any plans for saturday afternoon .
Person2:A friend and I are planing to go out , why ? what's up ?
Person1: There is a special exhibition of french sculptures at the museum , I was hoping you ' d like to come with me .
Person2:I am afraid I can't I am going to be out all day .
Person1: What about sunday ?
Person2:I wish I could , but it's my mums birthday .
Person1: Maybe next week .
Person2:Much as I ' d like to , I am afraid i wont be free next week , I have a lot of work .
Person1: Sorry to hear that , I was really looking forward to spending some more time with you , I really enjoyed our last chat .
Person2:I am really sorry too , maybe I can give you a call sometime .

Answer:
informal