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:       John , I ’ d like you to meet Charles Brown , our new manager at the airport .  
 Person2:Yes , certainly . How can I recognize him ?  
 Person1:        He is short , well-built , and he ’ s got light blond hair .  
 Person2:Is there anything else ?  
 Person1:        He has a mustache , if I remember correctly , and a light complexion .  
 Person2:How old is he ?  
 Person1:        He is in his late thirties .  
 Person2:Well . I shouldn ’ t have any trouble recognizing him . What time does his flight arrive ?  
 Person1:        At two thirty . 

formal