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:       We're supposed to check in at the Air China's counter 30 minutes before take-off , Joe .  
 Person2:Yes , I know . The boarding time on the ticket says 17:05 , and now it's 16:15 . I guess we have plenty of time .  
 Person1:        Do we need to show our ID cards when checking in ?  
 Person2:Yes.It ' s essential .  
 Person1:        What about our luggage ?  
 Person2:We can check it and hand carry the small bags . And we have to open each for inspection .  
 Person1:        Are they going to frisk all the passengers ?  
 Person2:I think so.We certainly don't want a hijack to happen on the plane today . 

formal