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:       Good morning . I've come here to inquire whether I can get a visa to your country ?  
 Person2:What do you want to go to US for ?  
 Person1:        I have been invited to teach Chinese at the University of Hawaii for two years .  
 Person2:Can I have a look at your letter of acceptance ?  
 Person1:        Of course . Here you are .  
 Person2:That's OK . We'll contact you the moment we hear from home . 

formal