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: Good evening , sir . What's your pleasure this evening ? Your usual ?
Person2:Yes . I'm going to stay with the same , a beer .
Person1: Certainly , a beer . Here you are , sir .
Person2:Oh , darn . Look what I've done . ( Spill the drink )
Person1: Don't worry . I'll make you another on the house .
Example Output: informal

Example Input: Person1: Hello !
Person2:Is that the box-office ?
Person1: Yes .
Person2:I'd like to book two tickets for the film ' Jane Eyre ' for this evening , please .
Person1: Just a minute please . Oh , I'm sorry , all the tickets for tonight have been sold out .
Person2:What a pity ! How about tomorrow evening ?
Person1: Oh , you're lucky , there are just two tickets left . Do you want to take them ?
Person2:Wonderful , I'll take them .
Person1: OK , your name and telephone number please .
Person2:Wang Min . Telephone number is 13811658 . Can I pick the tickets this afternoon ?
Person1: Yes , of course .
Person2:Thank you very much .
Example Output: informal

Example Input: Person1: What do you do in summer ?
Person2:I love going out into the countryside for walks or bike ride . I love being out in the fresh summer air . How about you ?
Person1: I don ' t often go for walks , but I either play sports outside-you know , tennis or badminton-or just sit in the sunshine and read a good book .
Person2:What do you do in winter ?
Person1: Well , I play sports indoors quite often . If I ' m feeling lazy , I just watch a film at home . I prefer summer to winter .
Person2:I think most people do . I like wearing nice , colorful clothes in summer , you know , a nice dress or skirt . It ' s too cold for those kinds of clothes in winter .
Person1: Yes . I like wearing shorts in summer . My legs would freeze !
Person2:Do you think we ' ll have a nice summer this year ?
Person1: Thanks to global warming , it could be hotter than ever !
Example Output:
informal