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:       Is the environment a big issues in your country ? It is in mine .  
 Person2:It is in mine too.The biggest issue is water . The climate is dry and so water conservation is very important .  
 Person1:        What methods do you use to conserve water ?  
 Person2:Water is rationed . We can only use a certain amount each month . It means that we cannot use some modern household items , like washing machines . They use too much water .  
 Person1:        I see . I think the biggest environment problem in my country is air pollution .  
 Person2:Yes , I agree . The air here is much more polluted than in my country . Of course , my country is more agricultural and has much less industry .  
 Person1:        We have reduced emission of air pollutants in recent years , but cars are still a major source of them . Factories have become cleaner as stricter environment pollution law have been introduced .  
 Person2:The problem is now on a truly global scale . I don ’ t believe that any single country can do anything about it .  
 Person1:        I think you ’ re right . There needs to be an international response to this problem . 

formal