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:       Lisa wins the first prize in the English speech contest of her college .  
 Person2:Really ? That's really wonderful . I'm so happy for her .  
 Person1:        But I always feel disappointed . I have many problems with English learning .  
 Person2:Honey , cheer up .  
 Person1:        I feel confused about the grammars .  
 Person2:I'm sure you'll do fine if you try your best .  
 Person1:        And my writing is not good . I feel so frustrated .  
 Person2:Be confident , and never give up .  
 Person1:        I know that , mom . But sometimes I'm just sad .  
 Person2:Keep your chin up . Remember ? Nothing is impossible to a willing heart .  
 Person1:        Yes , mom . You are right . Nothing is impossible to a willing heart . I will keep going . 

informal