Definition: 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'.
Input:  Person1:       I ’ Ve decided to go to the cinema alone this evening . 
 Person2:What has caused you to make such a decision ? Didn ’ t you used to go with Helen ? 
 Person1:        Helen is nice but she talks a lot . 
 Person2:Oh . That ’ s really annoying when seeing a film . 
 Person1:        It sure is . 

formal