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:       How's your time spent in the United States ?  
 Person2:Well , pretty good .  
 Person1:        I'm glad to hear that . What impressed you most ?  
 Person2:Well , the cultural differences impressed me most .  
 Person1:        You mean we Chinese think differently from the Americans ?  
 Person2:That's right , quite different . One day one of my American friend looked pale , so I asked him whether he was sick or not . But he was reluctant to answer my question .  
 Person1:        That's weird .  
 Person2:And what's more , when he told me he had caught a cold for several days , I suggested him to go to the hospital as soon as possible .  
 Person1:        You really cared about your friend .  
 Person2:Sure I am . But he responded by saying'what do you mean ? ' .  
 Person1:        I'm confused . Why did he say that ?  
 Person2:I felt the same at first . Later he told me that I'd better not give him any suggestions when he was sick . Offering unsolicited help or advice is like showing sympathy to the weak or the poor . But back in China , helping others is always regarded being kind .  
 Person1:        Absolutely . Now I understand why he responded that way . 

formal