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:       Who's singing in your home , Jim ?  
 Person2:It's Ellie and her friends .  
 Person1:        Who's Ellie ?  
 Person2:She's my little niece.It ' s her birthday.They ' re singing " Happy Birthday " .  
 Person1:        Oh , I see.how old is she ?  
 Person2:She's ten .  
 Person1:        I suppose they're playing games .  
 Person2:Oh , yes.Ellie was playing games all day yesterday.By the way , Alice , when's your birthday ?  
 Person1:        Today .  
 Person2:Today ?  
 Person1:        Yes .  
 Person2:Well , imagine that ! How old are you ?  
 Person1:        Eighteen.Some friends are having a birthday party for me tonight.Do you want to come ?  
 Person2:Very much.What time ?  
 Person1:        About 6 .  
 Person2:I'll be at your house at about five thirty.Happy birthday . 

informal