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:       Mike , these flowers are just gorgeous .  
 Person2:I ’ m glad you like them . Happy birthday !  
 Person1:        I can ’ t thank you enough . I ’ m really touched . I don ’ t know what to say .  
 Person2:Forget it . It ’ s my pleasure . You mean a lot to me .  
 Person1:        You ’ re the best ! 

informal