instruction:
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'.
question:
Person1: Are these your text books ? Biochemistry , General Ecology , Botany , Cell Genetics , Molecular Genetics ...
Person2:Yes . I gotta review all of them for the final exam . It is just around the corner .
Person1: Oh , right ! Do you have many exams at the end of each semester ?
Person2:That depends . Some semesters have many , some don't . And some courses don't have exams but only ask for papers . That's easy .
Person1: And when do you prepare for your final exam ?
Person2:Honestly speaking , most students prepare it one month before the exam .
Person1: Really ? You only review your lessons in one month ? Does it work ?
Person2:Of course , it's useful . And it's very crucial to have the copies of teacher's notes , because most questions in the exam are based on them .
Person1: Wow , and all the key points are included in them ? You're so smart !
Person2:But the exam is not as simple as you may imagine . We have to stay up late .
Person1: Do you have the classrooms open for the whole night ?
Person2:Yes , some people even pack up his bed quilt and sleep there . That's a little bit crazy .
answer:
informal

question:
Person1: Hello , is this People's Theater ?
Person2:Yes , it is . May I help you ?
Person1: Yes , are advance tickets for ' Nut croakers ' still available ?
Person2:What date , sir ?
Person1: October 16th .
Person2:Let me see . Yes , we still have some tickets left . Which performance ?
Person1: 7:30 p . m . performance , please .
Person2:OK , we have tickets at 100 yuan and 50 yuan .
Person1: I'd like to reserve two seats at 100 yuan , please .
Person2:All right . May I have you name , please ?
Person1: Du Kun .
Person2:When would you like to collect the tickets ?
Person1: Tomorrow .
Person2:We can hold them until one day before the show .
Person1: How do we cancel , just in case ?
Person2:Just telephone us , and let us know in advance . We don't charge for cancellation .
Person1: All right , thank you very much . Good bye .
Person2:You are welcome . Goodbye .
answer:
informal

question:
Person1: Please tell us the exact time when the big fire broke out .
Person2:The exact time ? Let me think . You know , it happened at night .
Person1: But we need the exact time . What time ?
Person2:Oh , I remember . It was about 10 o'clock . When I was about to go to bed , suddenly I heard help outside .
answer:
informal