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:       Lisa , can I call Taiwan ?  
 Person2:Are you homesick ?  
 Person1:        I miss my parents .  
 Person2:Don't worry about the bill . Just call .  
 Person1:        Can you show me how to make an overseas call ?  
 Person2:Of course . First dial the code 011 to get an international line . Then you dial Taiwan's country code  
 Person1:        That's 886 .  
 Person2:Now you should know the rest . Don't forget to dial Taipei's city code . 

formal